Exposure apparatus and device manufacturing method

ABSTRACT

There is provided an exposure apparatus capable of accurately performing an exposure process and a measurement process based on a liquid immersion method. The exposure apparatus (EX), which forms a liquid immersion area (AR 2 ) of a liquid (LQ) on an image surface side of a projection optical system (PL), and exposes a substrate (P) via the projection optical system (PL) and the liquid (LQ) of the immersion area (AR 2 ), is provided with a measuring device ( 60 ) which measures at least one of a property and composition of the liquid (LQ) for forming the liquid immersion area (AR 2 ).

TECHNICAL FIELD

The present invention relates to an exposure apparatus that exposes asubstrate via a projection optical system and a liquid, and to a devicemanufacturing method.

This application claims the right of priority based on Japanese PatentApplication No. 2004-171115 filed on Jun. 9, 2004, the content of whichis hereby incorporated by reference.

BACKGROUND ART

Semiconductor devices and liquid crystal display devices aremanufactured by a so-called photolithographic method, in which a patternformed on a mask is transferred onto a photosensitive substrate. Anexposure apparatus used in the photolithographic process has a maskstage that supports a mask, and a substrate stage that supports asubstrate, and it transfer a pattern on the mask onto the substrate viaa projection optical system, while sequentially moving the mask stageand the substrate stage. Recently, higher resolution is desired for theprojection optical system, in order to address higher integration ofdevice patterns. The resolution of the projection optical systemincreases as an exposure wavelength to be used becomes shorter and anumerical aperture of the projection optical system becomes larger.Therefore, the exposure wavelength used in the exposure apparatusbecomes shorter year after year, and the numerical aperture increases aswell. The exposure wavelength, which is dominantly used at present, is248 nm of a KrF excimer laser. However, the exposure wavelength of 193nm of the ArF excimer laser, which is shorter than the above, is alsopractically used.

When the exposure is performed, depth of focus (DOF) is important aswell as the resolution. The resolution R and the depth of focus δ arerespectively expressed by the following expressions:

R=k ₁ ·λ/NA  (1)

δ=±k ₂ ·λ/NA ²  (2)

Here, λ represents the exposure wavelength, NA represents the numericalaperture of the projection optical system, and k₁ and k₂ representsprocess coefficients. From the expressions (1) and (2), it is seen thatif the exposure wavelength λ is shortened and the numerical aperture NAis increased in order to enhance the resolution R, then the depth offocus δ becomes narrow.

If the depth of focus δ becomes too narrow, it is difficult to align thesubstrate with respect to the image surface of the projection opticalsystem, and a focus margin during the exposure operation may beinsufficient. Accordingly, the liquid immersion method has beensuggested, which is disclosed, for example, in Patent Document 1described below as a method for substantially shortening the exposurewavelength and widening the depth of focus. According to this liquidimmersion method, the space between a bottom surface of the projectionoptical system and the substrate surface is filled with a liquid such aswater or any organic solvent to form a liquid immersion area, to improvethe resolution and, at the same time, enlarge the depth of focus byapproximately n times by taking advantage of the fact that thewavelength of the exposure light in the liquid becomes 1/n times that inthe air (n represents the refractive index of the liquid, and isgenerally about 1.2 to 1.6).

Patent Document 1: PCT International Publication No. WO99/49504

DISCLOSURE OF INVENTION Problems Solved by the Invention

In the liquid immersion method, however, it is important to maintain theliquid in a desired state, in order to perform an exposure process and ameasurement process via the liquid accurately. Therefore, when there issome deficiency in the liquid or in the exposure process and themeasurement process via the liquid, it is important to take appropriatemeasures quickly addressing the problem.

In view of the above situation, it is an object of the present inventionto provide an exposure apparatus that can accurately perform theexposure process and the measurement process based on the liquidimmersion method, and a device manufacturing method.

Means for Solving the Problems

To solve the above problems, the present invention adopts the followingconfiguration corresponding to FIGS. 1 to 9 shown in the embodiment.

An exposure apparatus (EX) of the present invention is an exposureapparatus, which forms a liquid immersion area (AR2) of a liquid (LQ) onan image surface side of a projection optical system (PL), and exposes asubstrate (P) via the projection optical system (PL) and the liquid (LQ)of the liquid immersion area (AR2), comprising a measuring device (60)which measures at least one of a property and composition of the liquid(LQ) for forming the liquid immersion area (AR2).

According to the present invention, since the measuring device measuresat least one of the property and composition of the liquid, it can bedetermined whether the liquid is in a desired state based on themeasurement result. When the liquid has a problem, an appropriatemeasure can be taken quickly addressing the problem. Accordingly, theexposure process and the measurement process via the liquid can beaccurately performed.

Here, items of the property and composition of the liquid to be measuredby the measuring device include a specific resistance value of theliquid, total organic carbon (TOC) in the liquid, particles or foreignmatter including bubbles contained in the liquid, dissolved gascontaining dissolved oxygen (DO) and dissolved nitrogen (DN), silicaconcentration in the liquid, and live bacteria in the liquid.

An exposure apparatus (EX) of the present invention is an exposureapparatus, which forms a liquid immersion area (AR2) of a liquid (LQ) onan image surface side of a projection optical system (PL), and exposes asubstrate (P) via the projection optical system (PL) and the liquid (LQ)of the liquid immersion area (AR2), comprising a functional liquidsupply device (120) which supplies a functional liquid having apredetermined function to a predetermined member (2, 13, 23, 33, 51, and70) in contact with the liquid (LQ).

According to the present invention, since the functional liquid supplydevice supplies the functional liquid to the predetermined member incontact with the liquid, the predetermined member can be made in thedesired state relative to the liquid. Accordingly, even when there is aproblem in the predetermined member or the liquid in contact with thepredetermined member, the liquid in contact with the predeterminedmember can be maintained in or changed to the desired state by supplyingthe functional liquid addressing the problem. As a result, the exposureprocess and the measurement process via the liquid can be accuratelyperformed.

An exposure apparatus (EX) of the present invention is an exposureapparatus, which forms a liquid immersion area (AR2) of a liquid (LQ) onan image surface side of a projection optical system (PL) andsequentially exposes a plurality of shot areas (S1 to S24) set on asubstrate (P) via the projection optical system (PL) and the liquid (LQ)of the liquid immersion area (AR2), comprising a liquid supply mechanism(10) for supplying a liquid (LQ), a first liquid recovery mechanism (20)for recovering the liquid (LQ), a second liquid recovery mechanism (30)for recovering the liquid (LQ), which is not recovered by the firstliquid recovery mechanism (20), a detector (90) which detects whetherthe second liquid recovery mechanism (30) has recovered the liquid (LQ),and a storage device (MRY) which stores a detection result of thedetector (90) in correspondence with the shot areas (S1 to S24).

According to the present invention, the second liquid recovery mechanismdetects whether the liquid has been recovered by using the detector, andthe storage device stores the detection result in correspondence withthe shot areas on the substrate. Accordingly, the cause of the problemgenerated on the shot area can be analyzed by using the storage deviceinformation in the storage device. In other words, in a shot areaexposed when the second liquid recovery mechanism has recovered theliquid, there is concern that a problem may occur such that the exposureaccuracy in the shot area deteriorates. In this case, the cause of theproblem can be specified by using the memory information. Therefore, anappropriate measure can be taken quickly corresponding to the specifiedcause of the problem, thereby enabling to perform the exposure processand the measurement process via the liquid accurately.

A device manufacturing method according to the present invention usesthe exposure apparatus (EX) described above. According to the presentinvention, since devices can be manufactured in a state with theexposure accuracy and measurement accuracy being maintained well,devices exhibiting desired performance can be manufactured.

A maintenance method of the present invention is a maintenance method ofan exposure apparatus (EX) which forms a liquid immersion area (AR2) ofa liquid (LQ) on an image surface side of a projection optical system(PL), and exposes a substrate (P) via the projection optical system (PL)and the liquid in the liquid immersion area, and comprises a step forreplacing the liquid forming the liquid immersion area with a functionalliquid (LK) having a predetermined function. According to the presentinvention, a portion in contact with the liquid forming the liquidimmersion area can be maintained based on the predetermined function ofthe functional liquid.

ADVANTAGEOUS EFFECT OF THE INVENTION

According to the present invention, the exposure process and themeasurement process via the liquid can be performed accurately.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic block diagram showing one embodiment of anexposure apparatus of the present invention.

FIG. 2 is an enlarged diagram of the principal part of FIG. 1.

FIG. 3 is a schematic block diagram showing a liquid supply device.

FIG. 4 is a view of a substrate stage PST as viewed from the top.

FIG. 5 is a flowchart illustrating an exposure method according to thepresent invention.

FIG. 6A is a diagram illustrating a liquid recovery operation by firstand second liquid recovery mechanisms.

FIG. 6B is a diagram illustrating a liquid recovery operation by firstand second liquid recovery mechanisms.

FIG. 7 is an enlarged diagram of the principal part of anotherembodiment of the exposure apparatus of the present invention.

FIG. 8 is a flowchart showing one example of a maintenance method usinga functional liquid.

FIG. 9 is a flowchart showing one example of a manufacturing process ofsemiconductor devices.

DESCRIPTION OF THE REFERENCE SYMBOLS

-   -   2 optical element    -   2A liquid contact face    -   10 liquid supply mechanism    -   11 liquid supply device    -   12 supply outlet    -   13 supply pipe (supply channel, channel forming member)    -   13T timer    -   16 pure water production device    -   17 temperature controller    -   20 first liquid recovery mechanism    -   21 first liquid recovery device    -   22 first collection inlet    -   23 recovery pipe (recovery channel, channel forming member)    -   30 second liquid recovery mechanism    -   31 second liquid recovery device    -   32 second collection inlet    -   33 recovery pipe (recovery channel, channel forming member)    -   51 upper face    -   60 measuring device    -   61-64 meters (measuring devices)    -   61K-64K branch pipes (branch channels)    -   70 first nozzle member    -   70A liquid contact face    -   80 second nozzle member    -   80A liquid contact face    -   90 detector    -   120 functional liquid supply device (cleaning device)    -   161 pure water production unit (adjusting device)    -   162 ultra-pure water production unit (adjusting device)    -   173 degasifier (adjusting device)    -   174 filter (adjusting device)    -   300 measuring member (reference member)    -   400, 500, 600 light-measuring devices    -   AR1 projection area    -   AR2 liquid immersion area    -   EX exposure apparatus    -   INF notifying device    -   MRY storage device    -   LK functional liquid    -   LQ liquid    -   P substrate    -   PL projection optical system    -   PST substrate stage    -   S1-S24 shot areas    -   SB1-SB5 steps.

BEST MODE FOR CARRYING OUT THE INVENTION

The exposure apparatus of the present invention will be described withreference to the drawings. FIG. 1 is a schematic block diagram showingone embodiment of the exposure apparatus of the present invention.

In FIG. 1, the exposure apparatus EX comprises a mask stage MST movablewhile holding a mask M, a substrate stage PST movable while holding asubstrate P, an illumination optical system IL which illuminates themask M held on the mask stage MST with exposure light EL, a projectionoptical system PL which projection-exposes a pattern image of the mask Milluminated with the exposure light EL onto the substrate P held on thesubstrate stage PST, and a controller CONT which centrally controls thewhole operation of the exposure apparatus EX. A notifying device INF forreporting information relating to the exposure process is connected tothe controller CONT. The notifying device INF includes an alarm devicewhich issues a signal (warning) by using a display device, or by meansof sound or light. The notifying device INF is further connected to astorage device MRY for storing information relating the exposureprocess. The entire exposure apparatus EX is driven by power from acommercial power supply (first driving source) 100A supplied from apower company.

The exposure apparatus EX in this embodiment is a liquid immersionexposure apparatus applying the liquid immersion method in order toimprove the resolution by substantially shortening the exposurewavelength, and to widen the depth of focus substantially, whichcomprises a liquid supply mechanism 10 for supplying a liquid LQ to animage surface side of the projection optical system PL, a first liquidrecovery mechanism 20 and a second liquid recovery mechanism 30 forrecovering the liquid LQ. The exposure apparatus EX locally forms aliquid immersion area AR2 larger than a projection area AR1 and smallerthan the substrate P, on a part of the substrate P including theprojection area AR1 of the projection optical system PL by the liquid LQsupplied from the liquid supply mechanism 10, at least whiletransferring the pattern image of the mask M to the substrate P.Specifically, the exposure apparatus EX adopts a local liquid immersionmethod in which the liquid LQ is filled in a space between the opticalelement 2 at the end of the image surface side of the projection opticalsystem PL and the surface of the substrate P arranged on the imagesurface side, and the pattern on the mask M is projection-exposed on thesubstrate P by irradiating the exposure light EL having passed throughthe mask M to the substrate P via the liquid LQ between the projectionoptical system PL and the substrate P and the projection optical systemPL. The controller CONT supplies the liquid LQ onto the substrate P in apredetermined amount by using the liquid supply mechanism 10, andrecovers the liquid LQ on the substrate P in a predetermined amount byusing the first liquid recovery mechanism 20, thereby locally formingthe liquid immersion area AR2 of the liquid LQ on the substrate P.Moreover, the second liquid recovery mechanism 30 recovers the liquidLQ, which cannot be recovered by the first liquid recovery mechanism 20.

The exposure apparatus EX further comprises a measuring device 60 formeasuring at least one of the property and composition of the liquid LQfor forming the liquid immersion area AR2. In the embodiment, themeasuring device 60 measures the liquid LQ supplied by the liquid supplymechanism 10. The liquid supply mechanism 10 includes a functionalliquid supply device 120 capable of supplying a functional liquid havinga predetermined function separate from the liquid LQ for forming theliquid immersion area AR2. The exposure apparatus EX further comprises adetector 90 for detecting whether the second liquid recovery mechanism30 has recovered the liquid LQ.

A first nozzle member 70 described later in detail is arranged near theimage surface side of the projection optical system PL, morespecifically, near the optical element 2 at the end of the image surfaceside of the projection optical system PL. The first nozzle member 70 isan annular member provided so as to surround the optical element 2 abovethe substrate P (the substrate stage PST). A second nozzle member 80separate from the first nozzle member 70 is arranged outside of thefirst nozzle member 70, with respect to the projection area AR1 of theprojection optical system PL. The second nozzle member 80 is an annularmember provided so as to surround the first nozzle member 70 above thesubstrate P (the substrate stage PST). In the embodiment, the firstnozzle member 70 constitutes a part of the liquid supply mechanism 10and the first liquid recovery mechanism 20. On the other hand, thesecond nozzle member 80 constitutes a part of the second liquid recoverymechanism 30.

In the embodiment, a case in which a scanning type exposure apparatus (aso-called scanning stepper), which exposes a pattern formed on the maskM on the substrate P while synchronously moving the mask M and thesubstrate P in different directions (to opposite directions) in thescanning direction, is used as the exposure apparatus EX, is describedas an example. In the following description, the direction that matchesthe optical axis AX of the projection optical system PL is designated asthe Z-axis direction, the synchronous movement direction (scanningdirection) of the mask M and the substrate P within a planeperpendicular to the Z-axis direction is designated as the X-axisdirection, and the direction (non-scanning direction) perpendicular tothe Z-axis direction and the X-axis direction is designated as theY-axis direction. Moreover, rotation (inclination) directions about theX axis, Y axis, and Z axis are respectively designated as the θX, θY,and θZ directions.

The exposure apparatus EX includes a base BP provided on the floor, anda main column 1 installed on the base BP. On the main column 1 areformed an upper step 7 and a lower step 8 protruding inward. Theillumination optical system IL is for illuminating the mask M supportedon the mask stage MST with the exposure light EL, and is supported by asupport frame 3 fixed to an upper part of the main column 1.

The illumination optical system IL has; an exposure light source, anoptical integrator which equalizes illuminance of beams emitted from theexposure light source, a condenser lens which focuses the exposure lightEL from the optical integrator, a relay lens system, and a variablefield stop for setting an illumination area on the mask M by theexposure light EL in a slit shape. The predetermined illumination areaon the mask M is illuminated with the exposure light EL having a uniformillumination distribution, from the illumination optical system IL. Asthe exposure light EL radiated from the illumination optical system IL,emission lines (g-ray, h-ray, i-ray) in the ultraviolet region radiated,for example, from a mercury lamp, deep ultraviolet light beams (DUWlight beams) such as the KrF excimer laser beam (wavelength: 248 nm),and vacuum ultraviolet light beams (VUV light beams) such as the ArFexcimer laser beam (wavelength: 193 nm) and the F₂ laser beam(wavelength: 157 nm) are used. In this embodiment, the ArF excimer laserbeam is used.

In the embodiment, pure water is used as the liquid LQ. The pure watercan transmit not only the ArF excimer laser beam but also the emissionlines (g-ray, h-ray, i-ray) in the ultraviolet region radiated, forexample, from a mercury lamp, and the deep ultraviolet light (DUV lightbeams) such as the KrF excimer laser beam (wavelength: 248 nm).

The mask stage MST can move, while holding the mask M. The mask stageMST holds the mask M by vacuum suction (electrostatic attraction). Aplurality of air bearings 45, being non-contact bearings, is provided onthe bottom surface of the mask stage MST. The mask stage MST issupported in a non-contact manner relative to the upper face (guideface) of a mask board 4 by the air bearings 45. Openings MK1 and MK2 forallowing the pattern image of the mask M to pass through arerespectively formed in the center of the mask stage MST and the maskboard 4. The mask board 4 is supported on the upper step 7 of the maincolumn 1 via an isolator 46. In other words, the mask stage MST issupported by the main column 1 (the upper step 7) via the isolator 46and the mask board 4. Moreover, the mask board 4 and the main column 1are vibrationally separated by the isolator 46 so that vibrations of themain column 1 are not transmitted to the mask board 4 supporting themask stage MST.

The mask stage MST can move two-dimensionally in a plane vertical to theoptical axis AX of the projection optical system PL, that is, in an XYplane, and can slightly rotate in the OZ direction, on the mask board 4,in the state of holding the mask M, driven by a mask stage drive MSTDincluding a linear motor controlled by the controller CONT. The maskstage MST can move at a specified scanning speed in the X-axisdirection, and has at least a movement stroke in the X-axis direction sothat the whole face of the mask M can cross the optical axis AX of theprojection optical system PL.

A movable mirror 41 is provided on the mask stage MST. A laserinterferometer 42 is provided at a position opposite to the movablemirror 41. A two-dimensional position of the mask M on the mask stageMST and an angle of rotation in the OZ direction (including angles ofrotation in the θX and θY directions according to circumstances) aremeasured by the laser interferometer 42 on a real time basis. Ameasurement result of the laser interferometer 42 is output to thecontroller CONT. The controller CONT drives the mask stage drive MSTDbased on the measurement result of the laser interferometer 42, tocontrol the position of the mask M held on the mask stage MST.

The projection optical system PL is for projection-exposing the patternof the mask M on the substrate P at a predetermined projectionmagnification β, and is formed of a plurality of optical elementsincluding the optical element 2 provided at the end on the substrate Pside, and these optical elements are supported by a lens-barrel PK. Inthe embodiment, the projection optical system PL is a reduction systemhaving the projection magnification β of, for example, ¼, ⅕, or ⅛. Theprojection optical system PL may be an equal magnification system or anenlarging system. The optical element 2 at the end of the projectionoptical system PL in the embodiment is exposed from the lens-barrel PK,and the liquid LQ in the liquid immersion area AR2 comes in contact withthe optical element 2.

A flange PF is provided on the outer periphery of the lens-barrel PKholding the projection optical system PL, and the projection opticalsystem PL is supported by a lens-barrel board 5 via the flange PF. Thelens-barrel board 5 is supported by the lower step 8 of the main column1 via an isolator 47. In other words, the projection optical system PLis supported by the main column 1 (the lower step 8) via the isolator 47and the lens-barrel board 5. Moreover, the lens-barrel board 5 and themain column 1 are vibrationally separated by the isolator 47 so thatvibrations of the main column 1 are not transmitted to the lens-barrelboard 5 supporting the projection optical system PL.

The substrate stage PST can move while supporting a substrate holder PHfor holding the substrate P. The substrate holder PH holds the substrateP by, for example, vacuum suction. A plurality of air bearings 48, beingnon-contact bearings, is provided on the bottom surface of the substratestage PST. The substrate stage PST is supported in a non-contact mannerrelative to the upper face (guide face) of a substrate board 6 by theair bearings 48. The substrate board 6 is supported on the base BP viaan isolator 49. Moreover, the substrate board 6 and the main column 1and the base BP are vibrationally separated from each other by theisolator 49 so that vibrations of the base BP (the floor) and the maincolumn 1 are not transmitted to the substrate board 6 supporting thesubstrate stage PST.

The substrate stage PST can move two-dimensionally in the XY plane, andcan slightly rotate in the OZ direction, on the substrate board 6, inthe state of holding the substrate P via the substrate holder PH, drivenby a substrate stage drive PSTD including a linear motor controlled bythe controller CONT. The substrate stage PST can further move in theZ-axis direction, the θX direction, and the θY direction.

A movable mirror 43 is provided on the substrate stage PST. A laserinterferometer 44 is provided at a position opposite to the movablemirror 43. A two-dimensional position of the substrate P on thesubstrate stage PST and an angle of rotation are measured by the laserinterferometer 44 on a real time basis. Though not shown, the exposureapparatus EX includes a grazing incidence focus/leveling detectionsystem, which detects position information of the surface of thesubstrate P supported on the substrate stage PST, such as the onedisclosed for example in Japanese Unexamined Patent Application, FirstPublication No. H08-37149. For the focus/leveling detection system, oneusing a capacitance type sensor can be adopted. The focus/levelingdetection system detects the position information of the surface of thesubstrate P in the Z-axis direction and the inclination information ofthe substrate P in the θX and θY directions.

A measurement result of the laser interferometer 44 is output to thecontroller CONT. A detection result of the focus/leveling detectionsystem is also output to the controller CONT. The controller CONT drivesthe substrate stage drive PSTD based on the detection result of thefocus/leveling detection system, to control the focus position and theinclination angle of the substrate P, so that the surface of thesubstrate P is matched with the image surface of the projection opticalsystem PL according to an auto-focus method and an auto-leveling method,and also controls the position of the substrate P in the X-axisdirection and the Y-axis direction based on the measurement result ofthe laser interferometer 44.

A depression 50 is provided in the substrate stage PST, and thesubstrate holder PH for holding the substrate P is arranged in thedepression 50. The upper face 51 of the substrate stage PST other thanthe depression 50 is a flat surface (flat portion) so as to be the sameheight as (to be flush with) the surface of the substrate P held in thesubstrate holder PH. In the embodiment, the upper face of the movablemirror 43 is also provided so as to be flush with the upper face 51 ofthe substrate stage PST.

Since the upper face 51 substantially flush with the surface of thesubstrate P is provided around the substrate P, even at the time ofperforming liquid immersion exposure of the edge area of the substrateP, there is actually no step portion outside of the edge of thesubstrate P. As a result, the liquid LQ is held on the image surfaceside of the projection optical system PL, to form the liquid immersionarea AR2 excellently. There is a gap of about 0.1 to 2 mm between theedge of the substrate P and the flat surface (upper face) 51 providedaround the substrate P. However, due to surface tension of the liquidLQ, the liquid LQ hardly flows into the gap, and even when the vicinityof the periphery of the substrate P is exposed, the liquid LQ can beheld below the projection optical system PL by the upper face 51.

The liquid supply mechanism 10 is for supplying the liquid LQ to theimage surface side of the projection optical system PL, and includes aliquid supply device 11 capable of feeding the liquid LQ and a supplypipe 13 connected to one end of the liquid supply device 11. The otherend of the supply pipe 13 is connected to the first nozzle member 70.

In the embodiment, the liquid supply mechanism 10 is for supplying purewater, and the liquid supply device 11 includes a pure water productiondevice 16 and a temperature controller 17 for controlling thetemperature of the liquid (pure water) LQ to be supplied. As the purewater production device, a pure water production device in a factory inwhich the exposure apparatus EX is installed may be used, withoutproviding the pure water production device in the exposure apparatus EX.In order to form the liquid immersion area AR2 on the substrate P, theliquid supply mechanism 10 supplies the liquid LQ in a predeterminedamount onto the substrate P arranged on the image surface side of theprojection optical system PL.

The measuring device 60, which measures at least one of the property andcomposition of the liquid LQ to be fed out from the liquid supply device11 and supplied to the image surface side of the projection opticalsystem PL, is provided somewhere in the supply pipe 13. As describedabove, the measuring device 60 comprises a device capable of measuringthe water quality in order to supply water as the liquid LQ.

The first liquid recovery mechanism 20 is for recovering the liquid LQon the image surface side of the projection optical system PL, andincludes a first liquid recovery device 21 capable of recovering theliquid LQ and a recovery pipe 23, one end of which is connected to thefirst liquid recovery device 21. The other end of the recovery pipe 23is connected to the first nozzle member 70. The first liquid recoverydevice 21 includes a vacuum system (suction device) 26 such as a vacuumpump, a gas-liquid separator 27 for separating the recovered liquid LQfrom the gas, and the like. As the vacuum system, a vacuum system in thefactory in which the exposure apparatus EX is installed may be used,without providing the vacuum pump in the exposure apparatus EX. In orderto form the liquid immersion area AR2 on the substrate P, the firstliquid recovery mechanism 20 recovers the liquid LQ on the substrate Psupplied from the liquid supply mechanism 10 in a predetermined amount.

The second liquid recovery mechanism 30 is for recovering the liquid LQon the image surface side of the projection optical system PL, andincludes a second liquid recovery device 31 capable of recovering theliquid LQ and a recovery pipe 33, one end of which is connected to thesecond liquid recovery device 31. The other end of the recovery pipe 33is connected to the second nozzle member 80. The second liquid recoverydevice 31 includes a vacuum system (suction device) 36 such as a vacuumpump, a gas-liquid separator 37 for separating the recovered liquid LQfrom the gas, and the like. As the vacuum system, the vacuum system inthe factory in which the exposure apparatus EX is installed may be used,without providing the vacuum pump in the exposure apparatus EX. Thesecond liquid recovery mechanism 30 can recover the liquid LQ, whichcannot be recovered by the first liquid recovery mechanism 20.

The second liquid recovery mechanism 30 has an uninterruptible powersupply (second driving source) 100B separate from the commercial powersupply 100A, which is a driving source of the entire exposure apparatusEX including the first liquid recovery mechanism 20. The uninterruptiblepower supply 100B supplies power (driving force) to a driving device ofthe second liquid recovery mechanism 30, for example, at the time ofpower failure of the commercial power supply 100A. For example, when thecommercial power supply 100A has a power failure, the second liquidrecovery device 31 in the second liquid recovery mechanism 30 is drivenby the power supplied from the uninterruptible power supply 100B. Inthis case, the liquid recovery operation of the second liquid recoverymechanism 30 including the second liquid recovery device 31 is notcontrolled by the controller CONT, but is controlled based on a commandsignal from another controller built, for example, in the second liquidrecovery mechanism 30.

At the time of power failure of the commercial power supply 100A, theuninterruptible power supply 100B can supply power also to thecontroller CONT in addition to the second liquid recovery mechanism 30.In this case, the controller CONT driven by the power from theuninterruptible power supply 100B can control the liquid recoveryoperation of the second liquid recovery mechanism 30. Moreover, thesecond liquid recovery mechanism 30 may be driven by the uninterruptiblepower supply 100B all the time. In this case, the first liquid recoverymechanism 20 and the second liquid recovery mechanism 30 arerespectively driven by the separate power supplies 100A and 100B.

In the embodiment, the liquid LQ recovered by the first liquid recoverymechanism 20 and the second liquid recovery mechanism 30 is returned tothe liquid supply device 11 in the liquid supply mechanism 10. In otherwords, the exposure apparatus EX in the embodiment includes acirculatory system, which circulates the liquid LQ between the liquidsupply mechanism 10, the first liquid recovery mechanism 20, and thesecond liquid recovery mechanism 30. The liquid LQ returned to theliquid supply device 11 in the liquid supply mechanism 10 is purified bythe pure water production device 16 and supplied again to the imagesurface side of the projection optical system PL (onto the substrate P).All or part of the liquid LQ recovered by the first and second liquidrecovery mechanisms 20 and 30 may be returned to the liquid supplymechanism 10. Alternatively, the liquid LQ recovered by the first andsecond liquid recovery mechanisms 20 and 30 may not be returned to theliquid supply mechanism 10, but the liquid LQ supplied from anothersupply source may be supplied, or tap water may be purified by the purewater production device 16 and then supplied to the image surface sideof the projection optical system PL. Moreover, the configuration may besuch that a first mode in which the recovered liquid LQ is purified andreturned to the liquid supply device 11 to be circulated, and a secondmode in which the recovered liquid LQ is disposed of, and new liquid LQis supplied from the liquid supply device 11, are changed over accordingto need.

The supply pipe 13 and the recovery pipe 23 are connected to each othervia a connection pipe 9. One end of the connection pipe 9 is connectedto a predetermined position somewhere along the supply pipe 13, and theother end thereof is connected to a predetermined position somewherealong the recovery pipe 23. A first valve 13B for opening and closing aflow channel of the supply pipe 13 is provided somewhere along thesupply pipe 13, a second valve 23B for opening and closing a flowchannel of the recovery pipe 23 is provided somewhere along the recoverypipe 23, and a third valve 9B for opening and closing a flow channel ofthe connection pipe 9 is provided somewhere along the connection pipe 9.The first valve 13B is provided in the supply pipe 13 on the firstnozzle member 70 side from the connection position with the connectionpipe 9, and the second valve 23B is provided in the recovery pipe 23 onthe first nozzle member 70 side from the connection position with theconnection pipe 9. The operation of the respective valves 13B, 23B, and9B is controlled by the controller CONT. The flow channel of the liquidLQ fed from the liquid supply device 11 is changed by these valves 13B,23B, and 9B.

A timer 13T is connected to the first valve 13B. The timer 13T canmeasure the time duration during which the first valve 13B is opened andthe time duration during which the first valve 13B is closed. Moreover,the timer 13T can detect whether the first valve 13B is closing the flowchannel of the supply pipe 13.

The timer 13T starts to measure the time, when the timer 13T detectsthat the first valve 13B has opened the flow channel of the supply pipe13. Moreover, the timer 13T can also start to measure the time, when thetimer 13T detects that the first valve 13B has closed the flow channelof the supply pipe 13.

The timer 13 can measure elapsed time since the first valve 13B openedthe flow channel of the supply pipe 13, that is, the elapsed time sincethe start of liquid supply by the liquid supply mechanism 10.Information relating to the elapsed time measured by the timer 13T isoutput to the controller CONT. The timer 13T stops the time measuringoperation when it detects that the first valve 13B has closed the flowchannel of the supply pipe 13, and resets the measured time (returns themeasured time to zero). Furthermore, the timer 13T can measure elapsedtime since the first valve 13B closed the flow channel of the supplypipe 13, that is, the elapsed time since suspension of liquid supply bythe liquid supply mechanism 10. Information relating to the elapsed timemeasured by the timer 13T is output to the controller CONT. The timer13T stops the time measuring operation when it detects that the firstvalve 13B has opened the flow channel of the supply pipe 13, and resetsthe measured time (returns the measured time to zero).

The first nozzle member 70 constituting a part of the liquid supplymechanism 10 and the first liquid recovery mechanism 20 is held by afirst nozzle holding member 52, and the first nozzle holding member 52is connected to the lower step 8 of the main column 1. The second nozzlemember 80 constituting a part of the second liquid recovery mechanism 30is held by a second nozzle holding member 53, and the second nozzleholding member 53 is connected to the lower step 8 of the main column 1.The first nozzle holding member 52 and the second nozzle holding member53 are members independent of each other.

FIG. 2 is an enlarged diagram of the principal part, showing thevicinity of the image surface side of the projection optical system PL.In FIG. 2, the first nozzle member 70 is an annular member arranged nearthe optical element 2 at the end of the projection optical system PL soas to surround the optical element 2 above the substrate P (thesubstrate stage PST). The first nozzle member 70 has a hole 70H in whichthe projection optical system PL (the optical element 2) can be arrangedin the middle thereof. A bottom surface 70A of the first nozzle member70 is provided so as to face the substrate P held on the substrate stagePST. The first nozzle member 70 held by the first nozzle holding member52 (see FIG. 1) is away from the projection optical system PL (theoptical element 2). In other words, a gap is provided between the innerface of the first nozzle member 70, being an annular member, and theouter face of the optical element 2 of the projection optical system PL.The gap is provided for vibrationally separating the projection opticalsystem PL and the first nozzle member 70 from each other. As a result,vibrations generated by the first nozzle member 70 can be prevented frombeing transmitted to the projection optical system PL side.

The second nozzle member 80 is an annular member provided so as tosurround the first nozzle member 70 above the substrate P (the substratestage PST). The second nozzle member 80 has a hole 80H in which a partof the first nozzle member 70 can be arranged in the middle thereof. Abottom surface 80A of the second nozzle member 80 is provided so as toface the substrate P held on the substrate stage PST. The first nozzlemember 70 held by the first nozzle holding member 52 and the secondnozzle member 80 held by the second nozzle holding member 53 (seeFIG. 1) are away from each other. In other words, a gap is providedbetween the inner face of the second nozzle member 80, being an annularmember, and the outer face of the first nozzle member 70. The gap isprovided for vibrationally separating the first nozzle member 70 and thesecond nozzle member 80 from each other. As a result, vibrationsgenerated by the second nozzle member 80 can be prevented from beingtransmitted to the first nozzle member 70 side.

The main column 1 supporting the first and the second nozzle members 70and 80 via the first and the second nozzle holding members 52 and 53 andthe lens-barrel board 5 supporting the lens-barrel PK of the projectionoptical system PL via the flange PF, are vibrationally separated fromeach other via the isolator 47. Accordingly, a situation where thevibrations generated by the first nozzle member 70 and the second nozzlemember 80 are transmitted to the projection optical system PL isprevented. Moreover, the main column 1 supporting the first and thesecond nozzle members 70 and 80 via the first and the second nozzleholding members 52 and 53 and the substrate board 6 supporting thesubstrate stage PST are vibrationally separated from each other via theisolator 49. Accordingly, a situation where the vibrations generated bythe first nozzle member 70 and the second nozzle member 80 aretransmitted to the substrate stage PST via the main column 1 and thebase BP is prevented. Furthermore, the main column 1 supporting thefirst and the second nozzle members 70 and 80 via the first and thesecond nozzle holding members 52 and 53 and the mask board 4 supportingthe mask stage MST are vibrationally separated from each other via theisolator 46. Accordingly, a situation where the vibrations generated bythe first nozzle member 70 and the second nozzle member 80 aretransmitted to the mask stage MST via the main column 1 is prevented.

A supply outlet 12 (12A, 12B) constituting a part of the liquid supplymechanism 10 is provided in the bottom surface 70A of the first nozzlemember 70. In the embodiment, there are two supply outlets 12 (12A,12B), respectively provided in the opposite sides in the X-axisdirection, with the optical element 2 of the projection optical systemPL (projection area AR1) therebetween. In the embodiment, the supplyoutlets 12A and 12B are formed substantially in a circular shape, butmay be formed in an optional shape such as an elliptic shape, arectangular shape, or a slit shape. The supply outlets 12A and 12B maybe substantially in the same size, or may be in different sizes.

On the bottom surface 70A of the first nozzle member 70, a firstcollection inlet 22 constituting a part of the first liquid recoverymechanism 20 is provided outside of the supply outlet 12, relative tothe projection area AR1 of the projection optical system PL. The firstcollection inlet 22 is formed in an annular shape so as to surround theprojection area AR1 and the supply outlets 12A and 12B. The firstcollection inlet 22 is provided with a porous body 22P.

The other end of the supply pipe 13 is connected to one end of a supplychannel 14 formed in the first nozzle member 70. On the other hand, theother end of the supply channel 14 of the first nozzle member 70 isconnected to the supply outlet 12 formed in the bottom surface 70A ofthe first nozzle member 70. Here, the supply channel 14 formed in thefirst nozzle member 70 is branched somewhere so as to be connectable tothe plurality of (two) supply outlets (12A and 12B) at the other endsthereof.

The liquid supply operation of the liquid supply device 11 is controlledby the controller CONT. In order to form the liquid immersion area AR2,the controller CONT feeds the liquid LQ1 from the liquid supply device11 of the liquid supply mechanism 10. The liquid LQ fed out from theliquid supply device 11 flows in the supply pipe 13, and then flows intothe one end of the supply channel 14 formed in the first nozzle member70. The liquid LQ flowing into the one end of the supply channel 14 isbranched somewhere, and supplied to the space between the opticalelement 2 and the substrate P from the plurality of (two) supply outlets12A and 12B formed in the bottom surface 70A of the first nozzle member70.

The other end of the recovery pipe 23 is connected to one end of amanifold channel 24M constituting a part of the first recovery channel24 formed in the first nozzle member 70. On the other hand, the otherend of the manifold channel 24M is formed in an annular shape as seen inplan view so as to correspond to the first collection inlet 22, and isconnected to a part of an annular channel 24K constituting a part of thefirst recovery channel 24 connected to the first collection inlet 22.

The liquid recovery operation of the first liquid recovery device 21 iscontrolled by the controller CONT. The controller CONT drives the firstliquid recovery device 21 in the first liquid recovery mechanism 20 inorder to recover the liquid LQ. Due to the drive of the first liquidrecovery device 21 having the vacuum system 26, the liquid LQ on thesubstrate P flows into the annular channel 24K perpendicularly upward(in the +Z direction) via the first collection inlet 22 provided abovethe substrate P. The liquid LQ having flowed into the annular channel24K in the +Z direction is collected in the manifold channel 24M, andthen flows in the manifold channel 24M. Thereafter, the liquid LQ issucked and recovered by the first liquid recovery device 21 via therecovery pipe 23.

On the bottom surface 80A of the second nozzle member 80, a secondcollection inlet 32 constituting a part of the second liquid recoverymechanism 30 is provided. The second collection inlet 32 is formed inthe bottom surface 80A of the second nozzle member 80 opposite to thesubstrate P. The second nozzle member 80 is provided outside of thefirst nozzle member 70, and the second collection inlet 32 provided inthe second nozzle member 80 is provided further outside than the firstcollection inlet 22 provided in the first nozzle member 70, relative tothe projection area AR1 of the projection optical system PL. The secondcollection inlet 32 is formed in an annular shape so as to surround thefirst collection inlet 22.

The other end of the recovery pipe 33 is connected to one end of themanifold channel 34M constituting a part of the second recovery channel34 formed in the second nozzle member 80. On the other hand, the otherend of the manifold channel 34M is formed in an annular shape as seen inplan view so as to correspond to the second collection inlet 32, and isconnected to a part of an annular channel 34K constituting a part of thesecond recovery channel 34 connected to the second collection inlet 32.

The liquid recovery operation of the second liquid recovery device 31 iscontrolled by the controller CONT. The controller CONT drives the secondliquid recovery device 31 in the second liquid recovery mechanism 30 inorder to recover the liquid LQ. Due to the drive of the second liquidrecovery device 31 having the vacuum system 36, the liquid LQ on thesubstrate P flows into the annular channel 34K perpendicularly upward(in the +Z direction) via the second collection inlet 32 provided abovethe substrate P. The liquid LQ having flowed into the annular channel34K in the +Z direction is collected in the manifold channel 34M, andthen flows in the manifold channel 34M. Thereafter, the liquid LQ issucked and recovered by the second liquid recovery device 31 via therecovery pipe 33. In the embodiment, the controller CONT performs theliquid recovery operation (suction operation) by the second liquidrecovery mechanism 30 all the time during the liquid immersion exposureand before and after the exposure of the substrate P.

The measuring device 60 measures the property or composition (waterquality) of the liquid LQ supplied by the liquid supply mechanism 10.The property or composition of the liquid LQ measured by the measuringdevice 60 is determined, taking into consideration an influence on theexposure accuracy of the exposure apparatus EX or an influence on theexposure apparatus EX itself. Table 1 shows one example of the propertyor composition of the liquid LQ and the influence on the exposureaccuracy of the exposure apparatus EX or on the exposure apparatus EXitself. As shown in Table 1, the property or composition of the liquidLQ includes; specific resistance, metal ion, total organic carbon (TOC),particle bubbles, live bacteria, dissolved oxygen (DO), and dissolvednitrogen (DN). On the other hand, the items affecting the exposureaccuracy of the exposure apparatus EX or the exposure apparatus EXitself include; cloudiness of the lens (particularly, the opticalelement 2), generation of a water mark (remaining attachment due tosolidification of impurities in the liquid, resulting from evaporationof the liquid LQ), degradation of optical performance due to a change inrefractive index or light scattering, influence on a resist process(resist pattern formation), and generation of rust in respectivemembers. In Table 1, it is shown which property or composition affectswhich performance and how much, and a circle is given to an item, whichis expected to be affected. The property or composition of the liquid LQto be measured by the measuring device 60 is selected according torequirements from Table 1, based on the influence on the exposureaccuracy of the exposure apparatus EX or the exposure apparatus EXitself. It is a matter of course that all items can be measured, or aproperty or composition not shown in Table 1 can be also measured.

In order to measure the items selected from the above viewpoint, themeasuring device 60 has a plurality of meters. For example, themeasuring device 60 can include, as the meter, a resistivity meter formeasuring the specific resistance value, a TOC meter for measuring thetotal organic carbon, a particle counter for measuring foreign matterincluding fine particles and bubbles, a DO meter for measuring thedissolved oxygen (dissolved oxygen concentration), a DN meter formeasuring the dissolved nitrogen (dissolved nitrogen concentration), asilica meter for measuring concentration of silica, and an analyzercapable of analyzing the type and amount of the live bacteria. In theembodiment, as one example, the total organic carbon, particle bubbles,dissolved oxygen, and specific resistance value are selected as theitems to be measured, and as shown in FIG. 2, the measuring device 60includes a TOC meter 61 for measuring the total organic carbon, aparticle counter 62 for measuring foreign matter including fineparticles and bubbles, a dissolved oxygen meter (DO meter) 63 formeasuring the dissolved oxygen, and a resistivity meter 64 for measuringthe specific resistance value.

TABLE 1 Contents of influence Cloudiness of Optical Effluent Resist lensWatermark performance contamination process Rust Property/ Resistivity ◯◯ ◯ ◯ ◯ component Metal ion ◯ ◯ ◯ of liquid Total organic ◯ ◯ ◯ ◯ carbon(TOC) Particle bubbles ◯ ◯ ◯ ◯ Live bacteria ◯ ◯ ◯ ◯ Dissolved ◯ ◯ ◯oxygen (DO) Dissolved ◯ nitrogen (DN) Silica ◯ ◯ ◯ Organic Si ◯ ◯ ◯ ◯Anions ◯ ◯ ◯ ◯ ◯ Siloxane-based, ◯ ◯ ◯ ◯ ◯ CxHy-based Phthalic acid ◯ ◯◯ ◯ ◯ ester Cl ◯ ◯ ◯ ◯ ◯ PO₄, SO₄, NOx ◯ ◯ ◯ ◯ ◯ (PAG); Ammonia, ◯ ◯ ◯ ◯◯ amines Base resin ◯ ◯ ◯ ◯ ◯ Carboxylic ◯ ◯ ◯ ◯ ◯ acids (lactic acid,acetic acid, formic acid)

As shown in FIG. 2, the TOC meter 61 is connected to a branch pipe(branch channel) 61K branched somewhere along the supply pipe (supplychannel) 13 connected to the supply outlet 12. A part of the liquid LQfed out from the liquid supply device 11 and flowing in the supply pipe13 is supplied onto the substrate P from the supply outlet 12 of thefirst nozzle member 70, and a part of the remaining liquid LQ flows inthe branch pipe 61K and into the TOC meter 61. The TOC meter 61 measuresthe total organic carbon (TOC) of the liquid LQ flowing in the branchchannel formed by the branch pipe 61K. Likewise, the particle counter62, the dissolved oxygen meter 63, and the resistivity meter 64 arerespectively connected to respective branch pipes 62K, 63K, and 64Kbranched somewhere along the supply pipe 13, to measure foreign matter(fine particles or bubbles), dissolved oxygen, and the specificresistance value of the liquid LQ flowing in the branch channels formedby these branch pipes 62K, 63K, and 64K. The silica meter and/or thelive bacteria analyzer can be also connected to the branch pipe branchedsomewhere along the supply pipe 13.

In the embodiment, the branch pipes 61K to 64K respectively form anindependent branch channel, and respective meters 61 to 64 are connectedto respective branch channels independent of each other. In other words,a plurality of meters 61 to 64 is connected parallel with each otherrelative to the supply pipe 13 via the branch pipes 61K to 64K.According to the configuration of the meter, a plurality of meters maybe serially connected relative to the supply pipe 13, such that theliquid LQ branched from the supply pipe 13 is measured by a first meter,and the liquid LQ having passed the first meter is measured by a secondmeter. Since the possibility of generation of foreign matter (fineparticles) increases according to the number and position of the branchpipe (branch connection), the number and position of the branch pipeneeds to be set, taking the possibility of generation of foreign matterinto consideration. The same type of meters may be arranged at aplurality of positions along the supply pipe 13. According to such anarrangement, it can be specified at which position of the supply pipe 13the property or composition of the liquid LQ has changed, therebyfacilitating cause investigation of the change.

In the embodiment, the measuring device 60 measures the property orcomposition of the liquid LQ flowing in the branch channel branchedsomewhere along the supply channel formed by the supply pipe 13,according to an in-line method. By adopting the in-line method, theliquid LQ is supplied to the measuring device 60 all the time.Therefore, the measuring device 60 can measure the property orcomposition (water quality) of the liquid LQ all the time duringexposure and before and after the exposure. In other words, themeasuring device 60 can measure the liquid LQ, concurrently with theliquid immersion exposure operation to the substrate P. The measurementresult of the measuring device 60 is output to the controller CONT. Thecontroller CONT can monitor the property or composition (water quality)of the liquid LQ supplied onto the substrate P by the liquid supplymechanism 10 all the time.

In order to determine the type of metal ion contained in the liquid LQ,the liquid LQ is sampled, and by using an analyzer provided separatelyfrom the exposure apparatus EX, the type of the metal ion can bedetermined. As a result, an appropriate measure can be takencorresponding to the specified metal ion. Moreover, in order to measurethe impurities contained in the liquid LQ, the liquid LQ is sampled, andby using a total evaporative residue meter provided separately from theexposure apparatus EX, the total evaporative residue amount in theliquid LQ can be measured. In this case, the analyzer and the totalevaporative residue meter may automatically perform sampling of theliquid LQ regularly, and inform the type of the metal ion and themeasurement result of the total evaporative residue meter to theexposure apparatus EX. The exposure apparatus EX can compare theinformed measurement result with a reference value stored beforehand,and when the measurement result exceeds the reference value, can issue awarning.

The detector 90 detects whether the second liquid recovery mechanism 30has recovered the liquid LQ. In the embodiment, the detector 90 detectsoptically whether the liquid LQ is flowing in the recovery pipe 33 ofthe second liquid recovery mechanism 30, to thereby detect whether theliquid LQ has been recovered via the second collection inlet 32 of thesecond liquid recovery mechanism 30. The detector 90 includes afloodlight device 91 for emitting a detection beam La, and a lightreceiving device 92 for receiving the detection beam La. Transmissionwindows 93 and 94 capable of transmitting the detection beam La areprovided somewhere along the recovery pipe 33. The detector 90irradiates the detection beam La to the transmission window 93 from thefloodlight device 91. The detection beam La having transmitted throughthe transmission window 93 passes inside of the recovery pipe 33, and isthen received by the light receiving device 92 via the transmissionwindow 94. The light reception result of the light receiving device 92is output to the controller CONT. The light receiving amount by thelight receiving device 92 is different in a case where there is theliquid LQ in the recovery pipe 33 (on the optical path of the detectionbeams La) and in a case where there is no liquid LQ therein.Accordingly, the controller CONT can determine whether there is theliquid LQ (whether the liquid LQ is flowing) in the recovery pipe 33,that is, whether the second liquid recovery mechanism 30 has recoveredthe liquid LQ, based on the light reception result by the lightreceiving device 92.

The detector 90 needs only to detect whether the liquid LQ has beenrecovered via the second collection inlet 32, and for example, may be aliquid presence sensor provided inside of the recovery pipe 33. Theinstallation position of the liquid presence sensor is not limited tosomewhere along the recovery pipe 33, but may be near the secondcollection inlet 32 of the second nozzle member 80 or inside of thesecond recovery channel 34. Moreover, as the detector 90, for example, aflow rate controller (flow element) referred to as a mass flowcontroller may be provided somewhere along the recovery pipe 33, todetermine whether the liquid LQ has been recovered via the secondcollection inlet 32 based on the detection result of the mass flowcontroller.

Moreover, the detector 90 including the floodlight device and the lightreceiving device and the detector including the mass flow controller candetect the liquid recovery amount per unit time by the second liquidrecovery mechanism 30.

FIG. 3 shows the configuration of the liquid supply device 11 in detail.The liquid supply device 11 includes the pure water production device 16and the temperature controller 17 which controls the temperature of theliquid produced by the pure water production device 16. The pure waterproduction device 16 includes a pure water production unit 161 whichproduces pure water of predetermined purity by purifying waterincluding, for example, suspended matter and impurities, and anultra-pure water production unit 162 which produces pure water of highpurity (ultra-pure water) by removing impurities from the pure waterproduced by the pure water production unit 161. The pure waterproduction unit 161 (or the ultra-pure water production unit 162)includes a liquid reforming member such as an ion exchange membrane or aparticle filter, and a liquid reformer such as an ultravioletirradiation device (UV lamp), to control the specific resistance valueof the liquid, the amount of foreign matter (fine particles andbubbles), the total organic carbon, and the amount of live bacteria, todesired values by using the liquid reforming member and the liquidreformer.

As described above, the liquid LQ recovered by the first liquid recoverymechanism 20 and the second liquid recovery mechanism 30 is returned tothe liquid supply device 11 of the liquid supply mechanism 10.Specifically, the liquid LQ recovered by the first liquid recoverymechanism 20 and the second liquid recovery mechanism 30 is supplied tothe pure water production device 16 (the pure water production unit 161)in the liquid supply device 11 via a return pipe 18. The return pipe 18is provided with a valve 188B for opening and closing the flow channelof the return pipe 18. The pure water production device 16 purifies theliquid returned via the return pipe 18 by using the liquid reformingmember and the liquid reformer, and supplies the liquid to thetemperature controller 17. The functional liquid supply device 120 isconnected to the pure water production device 16 (the pure waterproduction unit 161) in the liquid supply device 11 via a supply pipe19. The functional liquid supply device 120 can supply a functionalliquid LK having a predetermined function separate from the liquid LQfor forming the liquid immersion area AR2. In the embodiment, thefunctional liquid supply device 120 supplies a liquid (functionalliquid) LK having a germicidal action. The supply pipe 19 is providedwith a valve 19B for opening and closing the flow channel of the supplypipe 19. The controller CONT operates the valve 19B to close the flowchannel of the supply pipe 19, to thereby suspend the supply of thefunctional liquid LK, when the valve 18B is operated to open the flowchannel of the return pipe 18 so as to supply the liquid LQ. On theother hand, when the valve 19B is operated to open the flow channel ofthe supply pipe 19, so as to supply the functional liquid LK, thecontroller CONT operates the valve 18B to close the flow channel of thereturn pipe 18, to thereby suspend the supply of the liquid LQ.

The temperature controller 17 controls the temperature of the liquid(pure water) LQ produced by the pure water production device 16 andsupplied to the supply pipe 13, and one end thereof is connected to thepure water production device 16 (the ultra-pure water production unit162), and the other end thereof is connected to the supply pipe 13.After controlling the temperature of the liquid LQ produced by the purewater production device 16, the temperature controller 17 feeds thetemperature-controlled liquid LQ to the supply pipe 13. The temperaturecontroller 17 includes a rough temperature controller 171 which roughlycontrols the temperature of the liquid LQ supplied from the ultra-purewater production unit 162 in the pure water production device 16, a flowrate controller 172 referred to as a mass flow controller and providedon the downstream side (supply pipe 13 side) of the flow channel of therough temperature controller 171 for controlling the amount of theliquid LQ per unit time to be allowed to flow to the supply pipe 13, adegasifier 173 for decreasing the concentration of the dissolved gas(dissolved oxygen concentration, dissolved nitrogen concentration) inthe liquid LQ having passed the flow rate controller 172, a filter 174for removing foreign matter (fine particles and bubbles) in the liquidLQ degasified by the degasifier 173, and a fine temperature controller175 for finely controlling the temperature of the liquid LQ havingpassed the filter 174.

The rough temperature controller 171 is for controlling the temperatureof the liquid LQ fed from the ultra-pure water production unit 162 withrough accuracy of about ±0.1° C. with respect to a target temperature(for example, 23° C.). The flow rate controller 172 is arranged betweenthe rough temperature controller 171 and the degasifier 173, andcontrols the flow rate per unit time of the liquid LQtemperature-controlled by the rough temperature controller 171 withrespect to the degasifier 173 side.

The degasifier 173 is arranged between the rough temperature controller171 and the fine temperature controller 175, specifically between theflow rate controller 172 and the filter 174, and degasifies the liquidLQ fed from the flow rate controller 172 to decrease the concentrationof the dissolved gas in the liquid LQ. For the degasifier 173, a knowndegasifier such as a decompressor, which degasifies by decompressing thesupplied liquid LQ, can be used. Moreover, an apparatus including adeaeration filter, which performs gas-liquid separation of the liquid LQby using a filter such as a hollow fiber membrane filter and removes theseparated gas component by using solid fibers, or an apparatus includinga deaeration pump, which performs gas-liquid separation of the liquid LQby using a centrifugal force and removes the separated gas component byusing solid fibers can be used as well. The degasifier 173 adjusts theconcentration of the dissolved gas to a desired value, by the liquidreforming member including the deaeration filter and the liquid reformerincluding the deaeration pump.

The filter 174 is arranged between the rough temperature controller 171and the fine temperature controller 175, specifically between thedegasifier 173 and the fine temperature controller 175, and removesforeign matter in the liquid LQ fed from the degasifier 173. There is apossibility that foreign matter (particles) is slightly mixed in theliquid LQ when the liquid LQ passes the flow rate controller 172 and thedegasifier 173, but by providing the filter 174 on the downstream side(the supply pipe 13 side) of the flow rate controller 172 and thedegasifier 173, the foreign matter can be removed by the filter 174. Forthe filter 174, a known filter such as the hollow fiber membrane filterand the particle filter can be used. The filter 174 including the liquidreforming member such as the particle filter adjusts the amount offoreign matter (fine particles and bubbles) in the liquid LQ to atolerance or below.

The fine temperature controller 175 is arranged between the roughtemperature controller 171 and the supply pipe 13, specifically betweenthe filter 174 and the supply pipe 13, and performs fine temperaturecontrol of the liquid LQ with high accuracy. For example, the finetemperature controller 175 finely adjusts the temperature (temperaturestability, temperature uniformity) of the liquid LQ fed from the filter174 with high accuracy of about +0.01° C. to +0.001° C. relative to atarget temperature. In the embodiment, of a plurality of equipmentconstituting the temperature controller 17, the fine temperaturecontroller 175 is arranged at a position closest to the substrate P,which is an object to which the liquid LQ is supplied, and hence, theliquid LQ temperature-controlled with high accuracy can be supplied tothe substrate P.

It is desired that the filter 174 is arranged between the roughtemperature controller 171 and the fine temperature controller 175 inthe temperature controller 17, but may be arranged at a differentposition in the temperature controller 17, or may be arranged outsidethe temperature controller 17.

As described above, the pure water production unit 161, the ultra-purewater production unit 162, the degasifier 173, and the filter 174respectively include the liquid reforming member and the liquidreformer, to constitute an adjusting device for regulating the waterquality (property or composition) of the liquid LQ. These respectivedevices 161, 162, and 174 are respectively provided at a plurality ofpredetermined positions of the flow channel, in which the liquid LQflows, of the liquid supply mechanism 10. In the embodiment, one liquidsupply device 11 is arranged with respect to one exposure apparatus EX(see FIG. 1), but the present invention is not limited thereto, and oneliquid supply device 11 may be shared by a plurality of exposureapparatuses EX. By having such a configuration, an area (footprint)occupied by the liquid supply device 11 can be reduced. Alternatively,the pure water production device 16 and the temperature controller 17constituting the liquid supply device 11 may be separated to share thepure water production device 16 by the plurality of exposure apparatusesEX, and the temperature controller 17 may be arranged for each exposureapparatus EX. According to this configuration, the footprint can bereduced, and temperature control for each exposure apparatus can berealized. In the above case, if the liquid supply device 11 or the purewater production device 16 shared by the plurality of exposureapparatuses EX is arranged on a floor (for example, under the floor)separate from the floor where the exposure apparatus EX is arranged, thespace of the clean room where the exposure apparatus EX is installed canbe used more effectively.

A method for exposing the pattern image of the mask M on the substrate Pby using the exposure apparatus EX having the above configuration willbe described with reference to the flowcharts in FIGS. 4 and 5.

FIG. 4 is a plan view of the substrate stage PST as viewed from the top.In FIG. 4, a plurality of shot areas S1 to S24 is set on the substrate Pcarried (loaded) onto the substrate stage PST by an unillustratedcarrier system (loader). An alignment mark AM is respectively added toeach of the shot areas S1 to S24 on the substrate P. A reference member(measuring member) 300 having a reference mark PFM to be measured by asubstrate alignment system, for example, disclosed in JapaneseUnexamined Patent Application, First Publication No. H04-65603, and areference mark MFM to be measured by a mask alignment system, forexample, disclosed in Japanese Unexamined Patent Application, FirstPublication No. H07-176468 is arranged at a predetermined position onthe substrate stage PST. Moreover, an illuminance unevenness sensor 400as disclosed in Japanese Unexamined Patent Application, FirstPublication No. S57-117238, a space image measuring sensor 500, asdisclosed in Japanese Unexamined Patent Application, First PublicationNo. 2002-14005, and an illuminance sensor 600, as disclosed in JapaneseUnexamined Patent Application, First Publication No. H11-16816, areprovided at predetermined positions on the substrate stage PST as lightmeasuring devices. The upper faces of the measuring member 300 and thelight measuring devices 400, 500, and 600 are substantially flush withthe upper face 51 of the substrate stage PST.

Before starting exposure of the substrate P, the controller CONTmeasures the position relation (baseline amount) between a detectionreference position of the substrate alignment system and a projectionposition of the pattern image of the mask M by using the substratealignment system, the mask alignment system, and the reference member300. The position of the substrate stage PST when the reference marksMFM and PFM on the reference member 300 are measured is measured by thelaser interferometer 44. Moreover, before starting exposure of thesubstrate P, the controller CONT performs a measurement process usingthe respective light measuring devices 400, 500, and 600 provided on thesubstrate stage PST, to perform various correction processes such aslens calibration and the like based on the measurement results.

For example, when a measurement process using the mask alignment systemis to be performed, the controller CONT performs position control of thesubstrate stage PST to make the projection optical system PL face thereference member 300, to thereby perform a liquid supply operation and aliquid recovery operation by the liquid supply mechanism 10 and thefirst liquid recovery mechanism 20, and measures the reference mark MFMon the reference member 300 via the projection optical system PL and theliquid LQ, in a state with the liquid immersion area AR2 of the liquidLQ being formed on the reference member 300. Likewise, when ameasurement process using respective light measuring devices 400, 500,and 600 is to be performed, the controller CONT performs a measurementprocess via the liquid LQ in a state with the liquid immersion area AR2of the liquid LQ being formed on the respective light measuring devices400, 500, and 600. When the liquid LQ is supplied onto the substratestage PST including the measuring member and the light measuring devicesfrom the liquid supply mechanism 10, the controller CONT drives thefirst valve 13B to open the flow channel of the supply pipe 13, in astate with the flow channel of the connection pipe 9 being closed by thethird valve 9B. When the liquid immersion area AR2 is formed, thecontroller CONT drives the second valve 23B to open the flow channel ofthe recovery pipe 23. Thus, in the measuring operation before theexposure, measurement via the liquid LQ is performed. When the liquidimmersion area AR2 is formed, the liquid LQ in the liquid immersion areaAR2 comes in contact with the bottom surface (liquid contact face) 2A ofthe optical element 2 of the projection optical system PL closest to theimage surface and the bottom surfaces (liquid contact faces) 70A and 80Aof the nozzle members 70 and 80. Furthermore, the liquid LQ comes incontact with the upper face 51 of the substrate stage PST including themeasuring member 300 and the light measuring devices 400, 500, and 600.

The controller CONT measures the alignment mark AM formed on each of theshot areas S1 to S24 on the substrate P by using the substrate alignmentsystem, in order to perform superposition exposure with respect to thesubstrate P. The position of the substrate stage PST when the substratealignment system measures the alignment mark AM is measured by the laserinterferometer 44. The controller CONT obtains position information ofthe shot areas S1 to S24 relative to the detection reference position ofthe substrate alignment system in a coordinate system specified by thelaser interferometer 44, based on the detection result of the alignmentmark AM, and moves the substrate stage PST based on the positioninformation and the baseline amount measured previously, to therebyadjust positions of the shot areas S1 and S24 with respect to theprojection position of the pattern image of the mask M. Here, in theembodiment, when the alignment mark AM and the reference mark PFM are tobe measured, the liquid immersion area AR2 is not formed on thesubstrate P (substrate stage PST), and the substrate alignment systemmeasures the alignment mark AM in a non-liquid immersion state (in a drystate). When the liquid immersion area AR2 is not formed on thesubstrate P (substrate stage PST), the controller CONT drives the thirdvalve 9B to open the flow channel of the connection pipe 9, in a statewith the flow channel of the supply pipe 13 being closed by the firstvalve 13B. As a result, the liquid LQ flowing from the liquid supplydevice 11 including the temperature controller 17 to the supply pipe 13flows to the recovery pipe 23 via the connection pipe 9.

That is, in the embodiment, the liquid supply device 11 including thetemperature controller 17 is driven all the time, and at the time ofsupplying the liquid to the image surface side of the projection opticalsystem PL, the controller CONT drives the first valve 13B to open theflow channel of the supply pipe 13, and closes the flow channel of theconnection pipe 9 by the third valve 9B, to thereby supply the liquid LQfed from the liquid supply device 11 to the image surface side of theprojection optical system PL. On the other hand, when it is notnecessary to supply the liquid to the image surface side of theprojection optical system PL, the controller CONT drives the third valve9B to open the flow channel of the connection pipe 9, and closes theflow channel of the supply pipe 13 by the first valve 13B, so that theliquid LQ fed from the liquid supply device 11 is not supplied to theimage surface side of the projection optical system PL, but is recoveredby the liquid recovery device 21 via the recovery pipe 23.

The controller CONT outputs a command signal to start liquid immersionexposure (step SA2). The controller CONT closes the flow channel of theconnection pipe 9 by the third valve 9B, in a state that the opticalelement 2 of the projection optical system PL faces the predeterminedarea on the substrate stage PST including the substrate P, and drivesthe first valve 13B to open the supply pipe 13, to thereby start supplyof the liquid LQ to the substrate P by the liquid supply mechanism 10.Moreover, the controller CONT starts liquid recovery by the first liquidrecovery mechanism 20, substantially simultaneously with the start ofsupply of the liquid LQ by the liquid supply mechanism 10. Here, theliquid supply amount per unit time by the liquid supply mechanism 10 andthe liquid recovery amount per unit time by the first liquid recoverymechanism 20 are approximately constant. The liquid LQ in the liquidimmersion area AR2 formed so as to perform liquid immersion exposurewith respect to the substrate P comes in contact with the bottom surface2A of the optical element 2 and the bottom surface 70A of the firstnozzle member 70. The liquid recovery operation (suction operation) bythe first liquid recovery mechanism 20 can be performed before startingthe liquid supply by the liquid supply mechanism 10 (even in the statewith liquid supply being suspended). As described above, the secondliquid recovery mechanism 30 is driven all the time, and the suctionoperation via the second collection inlet 32 by the second liquidrecovery mechanism 30 is performed all the time.

After a predetermined time has passed since the release of the firstvalve 13B and the liquid immersion area AR2 has been formed, thecontroller CONT irradiates the exposure light EL onto the substrate P ina state with the projection optical system PL facing the substrate P, sothat the pattern image of the mask M is exposed on the substrate P viathe projection optical system PL and the liquid LQ. Here, the reason whyexposure is not performed until the predetermined time has passed sincethe release of the first valve 13B is that there is concern that bubblesgenerated due to the operation of the valve may be left in the liquidimmersion area AR2 immediately after the release of the valve. When thesubstrate P is to be exposed, the controller CONT projection-exposes thepattern image of the mask M on the substrate P via the liquid LQ betweenthe projection optical system PL and the substrate P and the projectionoptical system PL, while performing recovery of the liquid LQ by thefirst liquid recovery mechanism 20 and moving the substrate stage PSTsupporting the substrate P in the X-axis direction (in the scanningdirection), concurrently with supply of the liquid LQ by the liquidsupply mechanism 10.

The exposure apparatus EX in the embodiment is for projection-exposingthe pattern image of the mask M, while moving the mask M and thesubstrate P in the X-axis direction (in the scanning direction). At thetime of scanning exposure, a part of the pattern image of the mask M isprojected in the projection area AR1 via the liquid LQ in the liquidimmersion area AR2 and the projection optical system PL, and thesubstrate P moves in the +X direction (or −X direction) relative to theprojection area AR1 at a speed of β·V (β is projection magnification),synchronously with the movement of the mask M in the −X direction (or +Xdirection) at a speed of V. After finishing exposure on one shot area ofa plurality of shot areas S1 to S24 set on the substrate P, the nextshot area moves to a scanning start position by stepping movement of thesubstrate P, and thereafter, the scanning exposure process with respectto respective shot areas S1 to S24 is sequentially performed, whilemoving the substrate P according to the step and scan method. When ashot area set in the boundary area of the substrate P (for example, shotarea S1, S4, S21, S24, or the like) is to be subjected to the liquidimmersion exposure, the liquid LQ in the liquid immersion area AR2larger than the projection area AR1 comes in contact with the upper face51 of the substrate stage PST.

During the liquid immersion exposure, the property or composition (waterquality) of the liquid LQ supplied on the substrate P by the liquidsupply mechanism 10 is measured (monitored) by the measuring device 60all the time. The measurement result of the measuring device 60 isoutput to the controller CONT, and the controller CONT stores themeasurement result (monitor information) of the measuring device 60 inthe storage device MRY (step SA3).

The controller CONT stores the measurement result of the measuringdevice 60 in correspondence with the time course, in the storage deviceMRY. The controller CONT can store the measurement result of themeasuring device 60 in correspondence with the time course in thestorage device MRY, for example, based on the output of the timer 13T,designating the time when the first valve 13B opens the flow channel ofthe supply pipe 13 as a measurement starting point (reference) of thetime course. In the description below, information in which themeasurement result of the measuring device 60 is stored incorrespondence with the time course is referred to as “first loginformation”.

The controller CONT further stores the measurement result of themeasuring device 60 in correspondence with the shot areas S1 to S24 tobe exposed, in the storage device MRY. The controller CONT can obtainposition information of the shot areas S1 to S24 in the coordinatesystem specified by the laser interferometer 44, for example, based onthe output of the laser interferometer 44, which measures the positionof the substrate stage PST, and store the measurement result of themeasuring device 60 at the time of exposing the shot area, whoseposition information has been obtained, in correspondence with the shotarea in the storage device MRY. A timewise deviation corresponding to adistance between a sampling port (branch pipe) of the measuring device60 and the supply outlet 12 occurs, between a point in time when themeasuring device 60 measures the liquid LQ and a point in time when themeasured liquid LQ is supplied onto the substrate P (shot area).Accordingly, the information to be stored in the storage device MRYneeds to be corrected, taking the distance into consideration. In thedescription below, the information in which the measurement result ofthe measuring device 60 is stored in correspondence with the shot areais referred to as “second log information”.

The controller CONT determines whether the measurement result of themeasuring device 60 is abnormal (step SA4). The controller CONT thencontrols the exposure operation based on the determination result.

Here, the measurement result of the measuring device 60 being abnormalindicates a situation in which a measurement of respective items(specific resistance value, TOC, foreign matter, dissolved gasconcentration, silica concentration, live bacteria, and the like) to bemeasured by the measuring device 60 is outside the tolerance, and theexposure process and the measurement process via the liquid LQ cannot beperformed in a desired state. For example, when the specific resistancevalue of the liquid LQ is smaller than a tolerance (abnormal) (as oneexample, 18.2 MΩ·cm at 25° C.), there is a possibility that metal ionssuch as sodium ions may be contained in a large amount in the liquid LQ.If the liquid immersion area AR2 is formed on the substrate P with theliquid LQ containing metal ions in a large amount, there is apossibility that the metal ions in the liquid LQ infiltrate into aphotosensitive material on the substrate P, and adhere on a devicepattern (wiring pattern) already formed below the photosensitivematerial, thereby causing malfunction of the device. If the ions in theliquid LQ are seen individually, when the metal ions are containedlarger than a tolerance (as one example, 3 ppt, more preferably, 1 ppt),when boron is contained larger than a tolerance (as one example, 3 ppt,more preferably, 1 ppt), when silica is contained larger than atolerance (as one example, 1 ppt, more preferably, 0.75 ppt), or whenanions are contained larger than a tolerance (as one example, 400 ppt),similar contamination occurs, and malfunction of the device may becaused. When the value of total organic carbon in the liquid LQ islarger than a tolerance (as one example, 5.0 ppb, more preferably, 1.0ppb), there is a possibility that light transmittance of the liquid LQmight be decreased. In this case, the exposure accuracy via the liquidLQ and the measurement accuracy by the light measuring device via theliquid LQ deteriorate. Specifically, when the light transmittance of theliquid LQ decreases, the exposure amount on the substrate P changes,thereby causing a difference in an exposure line width to be formed onthe substrate P. Moreover, due to a decrease in the light transmittance,the liquid LQ absorbs more optical energy by the decrease of the lighttransmittance, and hence, the liquid temperature increases. A differenceis generated in the focal length of the projection optical system PL,resulting from the temperature increase. Thus, a decrease of the lighttransmittance of the liquid LQ causes a deterioration of the exposureaccuracy. Therefore, taking these circumstances into consideration, apredetermined light transmittance is required for the liquid LQ, and thevalue of the total organic carbon (TOC) is specified correspondingthereto. As one example, the light transmittance required for the liquidLQ is equal to or higher than 99% per 1 mm of thickness of the liquidLQ, and the TOC required for the liquid LQ corresponding thereto isequal to or lower than 1.0 ppb. Moreover, when the amount of foreignmatter including fine particles and bubbles in the liquid LQ is largerthan a tolerance (abnormal) (as one example, 0.1 or more preferably 0.02particles and bubbles having a size of 0.1 μm or larger are included in1 milliliter), the possibility that a defect is caused in the patterntransferred to the substrate P via the liquid LQ increases. Furthermore,when the value of the dissolved gas including dissolved oxygen anddissolved nitrogen in the liquid LQ (dissolved gas concentration) islarger than a tolerance (abnormal) (as one example, 3 ppb or morepreferably 1 ppb in the case of dissolved oxygen, and 3 ppm in the caseof dissolved nitrogen), for example when the liquid LQ supplied onto thesubstrate P via the supply outlet 12 is released to the air, thepossibility that bubbles are generated in the liquid LQ due to thedissolved gas in the liquid LQ increases. If bubbles are generated inthe liquid LQ, the possibility that a defect is caused in the patterntransferred to the substrate P via the liquid LQ increases as well. Whenthe amount of live bacteria is larger than a tolerance (abnormal) (asone example, 1.0 cfu/L, more preferably, 0.1 cfu/L), the liquid LQ iscontaminated to deteriorate the light transmittance. Moreover, when theamount of live bacteria is large, the members coming in contact with theliquid LQ (nozzle member 70, optical element 2, substrate stage PST,supply pipe 13, recovery pipes 23 and 33, and the like) are alsocontaminated. When a photo acid generator (PAG) eluted from the resistis larger than a tolerance (as one example, 7.4×10⁻¹³ mol/cm²), and whenamines are larger than a tolerance (as one example, 3.1×10⁻¹³ mol/cm²),a water mark may adhere to the optical element 2 of the projectionoptical system PL or cloudiness may be generated.

During the liquid immersion exposure (during supply of the liquid LQ),when determined that the measurement result of the measuring device 60is normal, the controller CONT continues the liquid immersion operation(step SA5). On the other hand, during the liquid immersion exposure(during supply of the liquid LQ), when determined that the measurementresult of the measuring device 60 is abnormal, the controller CONT stopsthe exposure operation (step SA6). At this time, the controller CONT candrive the first valve 13B to close the flow channel of the supply pipe13, so as to suspend the supply of the liquid LQ. After suspending theexposure operation, the controller CONT may recover the liquid LQremaining on the substrate P by using the first nozzle member 70 and thefirst liquid recovery mechanism 20. In this case, the recovered liquidLQ may be disposed of without being returned to the liquid supply device1, and new liquid LQ may be injected to the liquid supply device 11 soas to replace the whole liquid LQ. Moreover, after the liquid LQremaining on the substrate P is recovered, the substrate P may becarried out (unloaded) from the substrate stage PST. This can prevent anundesirable situation such as where defective shots (defectivesubstrates) are formed in a large quantity resulting from continuance ofthe exposure process via the abnormal liquid LQ.

Furthermore, the controller CONT informs the measurement result(monitoring result) of the measuring device 60 by the notifying deviceINF (step SA7). For example, information relating to a variation amountof the TOC and the dissolved gas concentration in the liquid LQ with thelapse of time, and information relating to the TOC and the dissolved gasconcentration in the liquid LQ at the time of exposing a shot area (forexample, shot area S15) of the plurality of shot areas S1 to S24 can bedisplayed by the notifying device INF including a display device.Moreover, when determining that the measurement result of the measuringdevice 60 is abnormal, the controller CONT can inform that themeasurement result is abnormal by the notifying device INF, for example,by issuing an alarm (a warning) from the notifying device INF. Moreover,when the measuring device 60 has the same type of meters at a pluralityof positions along the supply pipe 13, the controller CONT can specifyin which section an abnormality has occurred based on the measurementresults of these meters. The controller CONT then can inform that anabnormality has occurred in a certain section by the notifying deviceINF, to urge an investigation of the section, thereby enabling earlyrecovery from the problem.

As described above, the liquid supply device 11 has the liquid reformingmember and the liquid reformer, and includes a plurality of adjustingdevices (pure water production unit 161, ultra-pure water productionunit 162, degasifier 163, and filter 164) for regulating the waterquality (property or composition) of the liquid LQ. The controller CONTcan specify at least one adjusting device from these adjusting devicesbased on the measurement result of the measuring device 60, and informinformation relating to the specified adjusting device by the notifyingdevice INF. For example, when determining that the dissolved gasconcentration is abnormal based on the measurement result of the DOmeter or the DN meter of the measuring device 60, the controller CONTdisplays (informs) a display of a content urging maintenance (inspectionand replacement) of, for example, the deaeration filter or thedeaeration pump of the degasifier 173, of the plurality of adjustingdevices by the notifying device INF. Moreover, when determining that thespecific resistance value of the liquid LQ is abnormal based on themeasurement result of the resistivity meter of the measuring device 60,the controller CONT displays (informs) a display of a content urgingmaintenance (inspection and replacement) of, for example, the pure waterproduction device of the plurality of adjusting devices. Whendetermining that the total organic carbon in the liquid LQ is abnormalbased on the measurement result of the TOC meter of the measuring device60, the controller CONT displays (informs) a display of a content urgingmaintenance (inspection and replacement) of, for example, the UV lamp ofthe pure water production device 16 of the plurality of adjustingdevices. When determining that the amount of foreign matter (fineparticles and bubbles) in the liquid LQ is abnormal based on themeasurement result of the particle counter of the measuring device 60,the controller CONT displays (informs) a display of a content urgingmaintenance (inspection and replacement) of, for example, the filter 174or the particle filter of the pure water production device 16 of theplurality of adjusting devices. When determining that the amount of livebacteria in the liquid LQ is abnormal based on the measurement result ofthe live bacteria analyzer of the measuring device 60, the controllerCONT displays (informs) a display of a content urging maintenance(inspection and replacement) of, for example, the UV lamp of the purewater production device 16 of the plurality of adjusting devices. Whendetermining that the concentration of silica in the liquid LQ isabnormal based on the measurement result of the silica meter of themeasuring device 60, the controller CONT displays (informs) a display ofa content urging maintenance (inspection and replacement) of, forexample, the filter for removing silica of the pure water productiondevice 16 of the plurality of adjusting devices. Furthermore, thecontroller CONT can control the valve 18B corresponding to the waterquality (property or composition) of the liquid LQ, to suspendcirculation of the liquid LQ. In this case, the controller CONT cancontrol so as to recover and dispose of the whole contaminated liquidLQ, and inject new liquid LQ to the liquid supply device 11 so as toreplace the liquid LQ in the system by the new liquid LQ.

The controller CONT can continue the exposure operation even when itdetermines that the liquid LQ has an abnormality. When the controllerCONT determines that the measurement result of the particle counter ofthe measuring device 60 is abnormal at the time of exposing, forexample, the shot area S15, the controller CONT stores the abnormalmeasurement result of the particle counter in correspondence with theshot area S15 as second log information in the storage device MRY. Afterall the shot areas S1 to S24 have been exposed, the controller CONT canremove the shot area S15 in which defective pattern transfer may haveoccurred due to the abnormality (existence of foreign matter) of theliquid LQ, or can control so that the shot area S15 is not exposed atthe time of the next superposition exposure. When the shot area S15 isinspected and if there is no abnormality in the formed pattern, thecontroller CONT continues device formation using the shot area S15,without removing the shot area S15. Alternatively, the controller CONTcan inform that the measurement result of the particle counter isabnormal, in correspondence with the shot area S15, by the notifyingdevice INF. Thus, the controller CONT can display the log information bythe notifying device INF, other than the configuration in which themeasurement result of the measuring device 60 is displayed by thenotifying device INF as the monitoring information on a real time basis.

Moreover, the controller CONT can control the exposure operation basedon the measurement result of the measuring device 60. For example, asdescribed above, before exposure of the substrate P, an exposure dose(illuminance) of the exposure light EL is measured by thelight-measuring device 600 (step SA1), and after the exposure dose(illuminance) of the exposure light EL is optimally set (corrected)based on the measurement result, the exposure operation is started.However, during the exposure of the substrate P, the light transmittanceof the liquid LQ may vary due to variations of the TOC in the liquid LQ.If the light transmittance of the liquid LQ changes, the exposure amount(accumulated exposure amount) on the substrate P changes, and as aresult, there may be a problem such that there is a difference in theexposure line width of the device pattern to be formed in the shotareas. Therefore, a relation between the TOC in the liquid LQ and thelight transmittance of the liquid LQ at that time is obtained and storedin advance in the storage device MRY, and the controller CONT controlsthe exposure amount based on the stored information and the measurementresult of the measuring device 60 (the TOC meter 61), thereby enablingprevention of the problem. In other words, the controller CONT derivesthe light transmittance corresponding to the change of the TOC in theliquid LQ based on the stored information, and controls so as to keepthe exposure amount on the substrate P constant. By controlling theexposure amount on the substrate P corresponding to the change of theTOC measured by the TOC meter 61, the exposure amount in the substrate(between shots) or between the substrates becomes constant, and hence, adifference in the exposure line width can be reduced.

The relation between the TOC and the light transmittance of the liquidLQ can be obtained by the measurement process via the liquid LQ usingthe light-measuring device 600. In the embodiment, since the laser isused as a light source of the exposure light EL, the exposure amount onthe substrate P can be controlled by using a method for controlling theenergy (luminous energy) per pulse or controlling the number of pulses.Alternatively, by controlling the scanning rate of the substrate P, theexposure amount on the substrate P can be controlled. The measuringoperation using the light-measuring device 600 (step SA1) is performedduring the exposure sequence, for every predetermined time interval, orfor every predetermined number of substrates to be processed, andcorrection control of the exposure amount described above is performedbetween the measuring operations during the exposure sequence, and isreset for each measuring operation.

As described above, since the measuring device 60 for measuring at leastone of the property and composition of the liquid LQ is provided, it canbe determined whether the liquid LQ for forming the liquid immersionarea AR2 is in a desired state (abnormal or not) based on themeasurement result. When the measurement result of the measuring device60 is abnormal, an appropriate measure for turning the liquid LQ intothe desired state can be taken quickly, or by controlling the exposureoperation, deterioration of the exposure accuracy can be prevented.Moreover, by turning the liquid LQ into the desired state based on themeasurement result of the measuring device 60, the accuracy of themeasurement process using the measuring member via the liquid LQ and thelight-measuring device can be maintained.

For example, when it is determined that the specific resistance value ofthe liquid LQ is abnormal based on the measurement result of theresistivity meter 64, by promptly taking an appropriate measure(maintenance of the ion-exchange membrane or the like) for setting thespecific resistance value to a desired value, a problem such asdefective operation of the device can be prevented. Likewise, when it isdetermined that the value of total organic carbon in the liquid LQ isabnormal based on the measurement result of the TOC meter 61, bypromptly taking an appropriate measure (maintenance of the UV lamp orthe like) for setting the value of total organic carbon to a desiredvalue, excellent exposure accuracy and measurement accuracy can bemaintained. Moreover, when it is determined that the amount of foreignmatter in the liquid LQ is abnormal based on the measurement result ofthe particle counter 62, by promptly taking an appropriate measure(maintenance of the particle filter or the like) for setting the amountof foreign matter to a desired value, occurrence of a problem such aswhere a defect occurs in the transferred pattern can be prevented. Whenit is determined that the value of the dissolved oxygen (dissolvednitrogen) in the liquid LQ is abnormal based on the measurement resultof the DO meter 63 (or the DN meter), by promptly taking an appropriatemeasure (maintenance of the deaeration pump or the like) for setting thevalue of the dissolved oxygen (dissolved nitrogen) to a desired value,generation of bubbles can be prevented and occurrence of a problem suchas where a defect occurs in the transferred pattern can be prevented.Likewise, by promptly taking an appropriate measure for setting thevalue of live bacteria to a desired value based on the analysis resultof the live bacteria analyzer, or by promptly taking an appropriatemeasure for setting the value of silica concentration to a desired valuebased on the measurement result of the silica meter, the water qualityof the liquid (pure water) can be maintained, and excellent exposureaccuracy and measurement accuracy via the liquid LQ can be maintained.

There is a possibility that the first liquid recovery mechanism 20cannot recover all of the liquid LQ during the liquid immersion exposureof the substrate P, and the liquid LQ flows outside of the firstcollection inlet 22. Moreover, there is a possibility that the firstliquid recovery mechanism 20 may have some abnormality and cannotperform the liquid recovery operation, or such a situation may occurthat the liquid supply mechanism 10 has some abnormality and has amalfunction, thereby supplying the liquid LQ in a large amount and theliquid LQ cannot be recovered only by the first liquid recoverymechanism 20. In this case, the second liquid recovery mechanism 30recovers the liquid LQ, which cannot be recovered by the first liquidrecovery mechanism 20 and flows outside of the first collection inlet22, via the second collection inlet 32. As shown in the diagram of FIG.6A, when the first liquid recovery mechanism 20 can recover all of theliquid LQ, the liquid LQ is not recovered from the second collectioninlet 32 of the second nozzle member 80, and only the gas (air) isrecovered. On the other hand, as shown in the diagram of FIG. 6B, whenthe first liquid recovery mechanism 20 cannot recover all of the liquidLQ, and the liquid LQ flows outside of the first collection inlet 22,the liquid LQ is recovered together with the ambient gas from the secondcollection inlet 32 of the second nozzle member 80. By providing thesecond liquid recovery mechanism 30, outflow of the liquid LQ from onthe substrate P (on the substrate stage PST) can be prevented.Therefore, generation of rust of the mechanical parts (members) andshort circuit of the drive system (peripheral device) due to theeffluent liquid LQ, or environmental change (humidity change and thelike) of the environment where the substrate P is placed due toevaporation of the effluent liquid LQ can be prevented, thereby enablingprevention of deterioration of the exposure accuracy and measurementaccuracy. Moreover, since the second liquid recovery mechanism 30 isdriven all the time and is performing the recovery operation (suctionoperation) all the time, the liquid LQ can be reliably recovered.

In the embodiment, the first liquid recovery mechanism 20 has such aconfiguration that large vibrations do not occur at the time ofrecovering the liquid LQ, since it recovers only the liquid LQ. On theother hand, the second liquid recovery mechanism 30 has such aconfiguration that the liquid LQ is recovered together with the ambientgas, and hence, when the liquid LQ is recovered together with theambient gas at the time of recovering the liquid LQ from the secondcollection inlet 32 of the second liquid recovery mechanism 30, there isa possibility that the recovered liquid LQ strikes against the recoverychannel and the inner wall of the recovery pipe in a droplet form,thereby causing vibrations in the second nozzle member 80. If vibrationsoccur in the second nozzle member 80, there is a possibility that thevibrations are transmitted to the first nozzle member 70 via the lowerstep 8 of the main column 1, to vibrate the liquid immersion area AR2 ofthe liquid LQ coming in contact with the first nozzle member 70, therebyvibrating the substrate P and the substrate stage PST coming in contactwith the liquid immersion area AR2.

As described above, though the second nozzle member 80 and theprojection optical system PL are vibrationally separated from each othervia the isolator 47, there is still a possibility that the vibrationsoccurring in the second nozzle member 80 may vibrate the projectionoptical system PL, to deteriorate the imaging characteristics via theprojection optical system PL and the liquid LQ. Moreover, there is apossibility that the liquid LQ in the liquid immersion area AR2 vibratesdue to the vibrations occurring in the second nozzle member 80, tothereby deteriorate the imaging characteristics due to the vibrations.

In the embodiment, the detector 90 detects (monitors) all the timewhether the second liquid recovery mechanism 30 has recovered the liquidLQ, during the liquid immersion exposure and during the measuringoperation via the liquid LQ (step SA1). The detection result of thedetector 90 is output to the controller CONT, and the controller CONTstores the detection result of the detector 90 (monitoring information)in the storage device MRY (step SA8).

The controller CONT stores the detection result of the detector 90 incorrespondence with the time course, in the storage device MRY. Thecontroller CONT can store the detection result of the detector 90 incorrespondence with the time course in the storage device MRY, forexample, based on the output of the timer 13T, designating the time whenthe first valve 13B opens the flow channel of the supply pipe 13 as themeasurement starting point (reference) of the time course. In thedescription below, information in which the detection result of thedetector 90 is stored in correspondence with the time course is referredto as “third log information”.

The controller CONT further stores the detection result of the detector90 in correspondence with the shot areas S1 to S24 to be exposed, in thestorage device MRY. The controller CONT can obtain position informationof the shot areas S1 to S24 in the coordinate system specified by thelaser interferometer 44, for example, based on the output of the laserinterferometer 44, which measures the position of the substrate stagePST, and store the detection result of the detector 90 at the time ofexposing the shot area, whose position information has been obtained, incorrespondence with the shot area in the storage device MRY. A timewisedeviation corresponding to a distance between a detection area of thedetector 90 (corresponding to the transmission windows 93 and 94) andthe second collection inlet 32 occurs, between a point in time when theliquid LQ on the substrate P (shot area) is recovered via the secondcollection inlet 32 and a point in time when the recovered liquid LQflows in the recovery pipe 23 and is detected by the detector 90.Accordingly, the information to be stored in the storage device MRYneeds to be corrected, taking the distance into consideration. In thedescription below, the information in which the detection result of thedetector 90 is stored in correspondence with the shot area is referredto as “fourth log information”.

Moreover, the detector 90 can detect a liquid recovery amount per unittime by the second liquid recovery mechanism 30. The controller CONTstores the information relating to the liquid recovery amount per unittime detected by the detector 90 in the storage device MRY. Theinformation relating to the liquid recovery amount per unit time can bestored in correspondence with the time course as the third loginformation, or in correspondence with the shot area as the fourth loginformation.

Since the detector 90 which detects whether the second liquid recoverymechanism 30 has recovered the liquid LQ is provided, it can bedetermined whether the state at the time of performing the liquidimmersion exposure is a desired state, based on the measurement resultthereof. In other words, the controller CONT can determine whethervibrations have occurred accompanying the liquid recovery operation ofthe second liquid recovery mechanism 30 at the time of exposing thesubstrate P (shot area), based on the detection result of the detector90. There is a high possibility that the pattern transfer accuracy maydeteriorate in a shot area where the pattern image of the mask M isexposed in the state that vibrations are occurring. Accordingly, thecontroller CONT can take an appropriate measure so as not to produce adefective shot (defective substrate) or in order to maintain excellentexposure accuracy and measurement accuracy, based on the detectionresult of the detector 90.

The controller CONT determines whether the second liquid recoverymechanism 30 has recovered the liquid LQ based on the detection resultof the detector 90 (step SA9). The controller CONT then controls theexposure operation based on the determination result. Specifically, whendetermining that the second liquid recovery mechanism 30 has notrecovered the liquid LQ during the liquid immersion exposure (duringsupply of the liquid LQ), the controller CONT continues the liquidimmersion exposure operation (step SA5). On the other hand, whendetermining that the second liquid recovery mechanism 30 has recoveredthe liquid LQ during the liquid immersion exposure (during supply of theliquid LQ), the controller CONT suspends the exposure operation (stepSA6). The substrate P may be carried out (unloaded) from the substratestage PST after suspension of the exposure operation. This can preventan undesirable situation such as where defective shots (defectivesubstrates) are formed in a large quantity resulting from continuance ofthe exposure process in the state that vibrations are occurringaccompanying the liquid recovery operation of the second liquid recoverymechanism 30.

Alternatively, for example, when determining that the second liquidrecovery mechanism 30 has recovered the liquid LQ based on the detectionresult of the detector 90, the controller CONT may suspend liquid supplyfrom the liquid supply mechanism 10. When the second liquid recoverymechanism 30 has recovered the liquid LQ, there is a high possibilitythat the liquid LQ is flowing out. In this case, therefore, bysuspending the liquid supply from the liquid supply mechanism 10,outflow of the liquid LQ can be prevented. Alternatively, whendetermining that the second liquid recovery mechanism 30 has recoveredthe liquid LQ, the controller CONT can suspend power supply, forexample, to electrical equipment including an actuator (a linear motor)for driving the substrate stage PST. When the second liquid recoverymechanism 30 has recovered the liquid LQ, there is a high possibilitythat the liquid LQ is flowing out. In this case, therefore, bysuspending power supply to the electrical equipment, occurrence of shortcircuit can be prevented, even if the effluent liquid LQ splashes ontothe electrical equipment.

The controller CONT also informs the detection result (monitoringinformation) of the detector 90 by the notifying device INF (step SA7).For example, the controller CONT may issue an alarm (a warning)indicating that the second liquid recovery mechanism 30 has recoveredthe liquid LQ from the notifying device INF including an alarm system.Alternatively, the controller CONT can display the information relatingto the liquid recovery amount per unit time by the second liquidrecovery mechanism 30, or information relating to whether the secondliquid recovery mechanism 30 has recovered the liquid LQ at the time ofexposing a certain shot area (for example, the shot area S15) of theplurality of shot areas S1 to S24, by the notifying device INF includingthe display device.

Moreover, since the detector 90 can detect the liquid recovery amountper unit time by the second liquid recovery mechanism 30, the notifyingdevice INF can also display the liquid recovery amount.

Furthermore, even when the controller CONT determines that the secondliquid recovery mechanism 30 has recovered the liquid LQ, the controllerCONT can continue the exposure operation. When determining that thesecond liquid recovery mechanism 30 has recovered the liquid LQ, forexample, at the time of exposing the shot area S15, the controller CONTstores the information that the second liquid recovery mechanism 30 hasrecovered the liquid LQ in correspondence with the shot area S15 as thefourth log information in the storage device MRY. After all the shotareas S1 to S24 have been exposed, the controller CONT can remove theshot area S15, in which defective pattern transfer may have occurred dueto liquid recovery by the second liquid recovery mechanism 30(occurrence of vibrations), or can take a measure so that the shot areaS15 is not exposed at the time of the next superposition exposure. Whenthe shot area S15 is inspected and if there is no abnormality in theformed pattern, the controller CONT continues device formation using theshot area S15, without removing the shot area S15. Alternatively, thecontroller CONT can inform that the second liquid recovery mechanism 30has recovered the liquid LQ at the time of exposing the shot area S15,in correspondence with the shot area S15 by the notifying device INF.Thus, the controller CONT can display the log information by thenotifying device INF, other than the configuration in which thedetection result of the detector 90 is displayed by the notifying deviceINF as the monitoring information on a real time basis.

In the case in which the exposure operation is continued even when thesecond liquid recovery mechanism 30 has recovered the liquid LQ, whenthe detector 90 detects that the second liquid recovery mechanism 30 hasrecovered the liquid LQ during exposure of the first shot area of theplurality of shot areas S1 to S24 set on the substrate P (for example,the shot area S15), the second shot area (S16) next to the first shotarea (S15) may be exposed, after waiting until the detector 90 cannotdetect the liquid anymore LQ. When the time while the second liquidrecovery mechanism 30 is recovering the liquid LQ, that is, the timewhen vibrations are occurring is long (for example, several seconds)relative to the irradiation time (for example, several hundredmilliseconds) of the exposure light EL with respect to one shot area, ifa plurality of shot areas is continuously exposed, these shot areas areexposed in the state that vibrations are occurring. Therefore, waitingtime is provided after the exposure of the first shot area, and afterwaiting until the detector 90 does not detect the liquid recovered bythe second liquid recovery mechanism 30 (after waiting until thevibrations subside), the exposure operation with respect to the shotarea is resumed, thereby suppressing the occurrence of a defective shot.For example, an acceleration sensor (vibration sensor) may be providedin the second nozzle member 80, and after the first shot area isexposed, the second shot area can be exposed after waiting until adetection value of the vibration sensor becomes equal to or lower than atolerance.

After finishing the liquid immersion exposure with respect to thesubstrate P, the controller CONT stops the supply of the liquid LQ viathe supply outlet 12 by the liquid supply mechanism 10. The controllerCONT then recovers the liquid LQ remaining on the substrate P and thesubstrate stage PST via the first collection inlet 22 of the firstliquid recovery mechanism 20 and the second collection inlet 32 of thesecond liquid recovery mechanism 30. After the recovery operation of theliquid LQ on the substrate P has finished, the substrate P subjected tothe exposure process is unloaded from the substrate stage PST (stepSA10).

After finishing the liquid immersion exposure, the controller CONTdrives the third valve 9B to open the flow channel of the connectionpipe 9, in the state with the flow channel of the supply pipe 13 beingclosed by the first valve 13B. This allows the liquid LQ flowing fromthe liquid supply device 11 including the temperature controller 17 tothe supply pipe 13 to flow to the recovery pipe 23 via the connectionpipe 9, and when it is not necessary to supply the liquid, the liquid LQfed from the liquid supply device 11 is not supplied onto the substrateP, but is recovered by the liquid recovery device 21 via the recoverypipe 23.

After the exposed substrate P is unloaded from the substrate stage PST,a new substrate P to be exposed is loaded on the substrate stage PST.Then, the above described exposure sequence is repeated. The first tothe fourth log information is accumulated and stored in the storagedevice MRY.

As described above, the first and the second log information relating tothe property or composition (water quality) of the liquid LQ, and thethird and the fourth log information relating to the liquid recoveryoperation (recovery situation) by the second liquid recovery mechanism30 are stored in the storage device MRY. By using these pieces of loginformation, analysis of defective exposure (error) and control of theexposure apparatus EX can be performed (step SA11).

For example, based on the first and the second log information,respective adjusting devices constituting the liquid supply device 11(the liquid reforming member and the liquid reformer) can be maintained(inspected and replaced) at an optimum timing. Moreover, based on thefirst and the second log information, the frequency of inspection andreplacement can be set optimally corresponding to the respectiveadjusting devices. For example, when it is found from the first loginformation that the measurement value of the particle counterdeteriorates with the lapse of time, optimal replacement timing(replacement frequency) of the particle filter can be predicted andoptimally set based on the degree of changes of the measurement valuewith the lapse of time. Furthermore, the performance of the particlefilter to be used can be optimally set based on the first loginformation. For example, when the measurement value of the particlecounter deteriorates rapidly with the lapse of time, a high-performanceparticle filter is used, and when the measurement value of the particlecounter does not change largely, a relatively low-performance (lowprice) particle filter can be used to reduce the cost.

Thus, by controlling the exposure apparatus EX based on the first andthe second log information, the occurrence of a problem such as whereexcessive (unnecessary) maintenance is performed, thereby decreasing theoperating ratio of the exposure apparatus, or on the contrary,maintenance is neglected, and the liquid LQ in the desired state cannotbe supplied, can be prevented.

Since the first log information is water quality information associatedwith the time course, it can be specified from which point in time thewater quality has deteriorated. Accordingly, the cause of generation ofdefective exposure can be analyzed in correspondence with the timecourse.

Moreover, the cause of problems (errors) such as defective exposure(pattern defect) can be analyzed by using the first and the second loginformation. Specifically, after the exposure of the substrate P, whenthe substrate P is inspected in a certain inspection process, which ispost-processing thereof, the cause of the problem can be analyzed andspecified by collating the inspection result with the first and thesecond log information, to perform analysis. For example, when defectiveexposure (pattern defect) has occurred in a large amount in a particularlot or in a particular shot area, the second log information is referredto, and when the measurement value of the particle counter at the timeof exposing the lot (or the shot area) shows an abnormal value, it canbe analyzed that the cause of the pattern defect is foreign matter (fineparticles and bubbles). Thus, by analyzing the correlation between thepattern defect and the foreign matter based on the first and the secondlog information, the cause of the problem (pattern defect) can bespecified. Based on the analysis result, an appropriate measure can betaken, such as replacing the particle filter or the deaeration filter soas not to generate a pattern defect. Likewise, by analyzing thecorrelation between defective device operation and the specificresistance value, and the correlation between the measurement value oflight transmittance of the liquid LQ by the light measuring device andthe TOC, by referring to the log information, the cause of variousproblems can be specified.

The controller CONT also controls the exposure operation and themeasurement operation based on the first and the second log information.For example, when it is determined that the value of TOC deteriorateswith the lapse of time based on the first log information, the exposureapparatus EX controls the exposure amount corresponding to the timecourse based on a value (variation) corresponding to the time course ofthe TOC stored as the first log information, thereby making the exposureamount constant between substrates P, to reduce a difference in theexposure line width. When the exposure amount is to be controlled amethod for controlling the energy (luminous energy) per pulse, a methodfor controlling the number of pulses, or a method for controlling thescanning speed of the substrate P can be employed.

The cause of problems (errors) such as defective exposure (a differencein line width) can be also analyzed by using the third and the fourthlog information. If vibrations are generated accompanying the liquidrecovery by the second liquid recovery mechanism 30, a difference(including a difference in line width in the substrate and a differencein line width in the shot) likely occurs in the exposure line width ofthe pattern. Specifically, after the exposure of the substrate P, whenthe substrate P is inspected in a certain inspection process, which ispost-processing thereof, the cause of the problem can be analyzed andspecified by collating the inspection result with the third and thefourth log information, to perform analysis. For example, when defectiveexposure (a difference in line width) has occurred in a large amount ina particular lot or in a particular shot area, the fourth loginformation is referred to, and when the second liquid recoverymechanism 30 recovers the liquid LQ at the time of exposing the lot (orthe shot area), it can be analyzed that the cause of the pattern defectis vibrations generated accompanying the liquid recovery operation bythe second liquid recovery mechanism 30. Thus, by analyzing thecorrelation between the detection result of the detector 90 (liquidrecovery state of the second liquid recovery mechanism 30) stored as thethird and the fourth log information and the changes in the line width,the influence of the liquid recovery operation by the second liquidrecovery mechanism 30 on the exposure accuracy is determined, and thecause of the problem (difference in line width) can be specified.

If vibrations occur accompanying the liquid recovery by the secondliquid recovery mechanism 30, accuracy of synchronous movement of themask M (the mask stage MST) and the substrate P (the substrate stagePST) or registration accuracy between the image surface of theprojection optical system PL via the liquid LQ and the surface of thesubstrate P (focus accuracy) deteriorates. Therefore, the informationrelating to the liquid recovery operation (recovery situation) of thesecond liquid recovery mechanism 30 is stored as the third and thefourth log information, and by analyzing the correlation between thedetection result of the detector 90 (the liquid recovery situation ofthe second liquid recovery mechanism 30) and the accuracy of synchronousmovement and the focus accuracy, the influence of the liquid recoveryoperation by the second liquid recovery mechanism 30 on the exposureaccuracy is determined, whereby the cause of the problem (deteriorationof the accuracy of synchronous movement and the focus accuracy) can bespecified.

Based on the analysis result, an appropriate measure can be taken suchthat the liquid supply amount per unit time by the liquid supplymechanism 10 is changed, the liquid recovery amount per unit time by thefirst liquid recovery mechanism 20 is changed, or the moving speed(scanning speed) of the substrate P is changed, so as not to generate adifference in the line width or the like, more specifically, so that thesecond liquid recovery mechanism 30 does not recover the liquid LQ,

Since the third log information is the information relating to theliquid recovery operation of the second liquid recovery mechanism 30associated with the time course, it can be specified at which point intime the liquid LQ has been recovered by the second liquid recoverymechanism 30. Therefore, the cause of generation of defective exposurecan be analyzed associated with the time course.

As described above, when it is determined that the liquid LQ is abnormalor the second liquid recovery mechanism 30 is recovering the liquidduring exposure of a particular shot area, based on the second loginformation or the fourth log information, the controller CONT can takea measure such that the particular shot area is removed, or the shotarea is not exposed at the time of next superposition exposure.Alternatively, the controller CONT can output an instruction to performmore detailed inspection of the particular shot area than usual, to aninspection device which performs the inspection process.

As described above, the influence of the liquid recovery operation bythe second liquid recovery mechanism 30 on the exposure accuracy(pattern transfer accuracy) can be determined by analyzing thecorrelation between the liquid recovery situation of the second liquidrecovery mechanism 30 and changes in the line width, or the correlationbetween the accuracy of synchronous movement and the focus accuracy. Asa result, the pattern transfer accuracy onto the substrate P when thesecond liquid recovery mechanism 30 recovers the liquid LQ can beobtained beforehand. Moreover, since the degree of deterioration of thepattern transfer accuracy changes corresponding to the liquid recoveryamount per unit time by the second liquid recovery mechanism 30, patterntransfer accuracy corresponding to the liquid recovery amount can beobtained beforehand. By storing the information relating to the patterntransfer accuracy when the second liquid recovery mechanism 30 recoversthe liquid LQ in the storage device MRY beforehand, the controller CONTcan predict the pattern transfer accuracy in a shot area on thesubstrate P, to which the pattern of the mask M has been transferredwhen the second liquid recovery mechanism 30 recovers the liquid LQ,based on the detection result of the detector 90 and the memoryinformation stored in the storage device MRY. Then the controller CONTcan inform the predicted result by the notifying device INF. As aresult, after the substrate P has been exposed, when it is predictedthat the predicted pattern transfer accuracy is equal to or higher thanthe tolerance, thereby causing a defective shot, the controller CONT cantake a measure such as removing the defective shot without going throughthe inspection process.

In the embodiment, for example, when it is desired to measure theconstituents of the live bacteria in the liquid LQ, the supplied liquidLQ may be sampled at a predetermined timing, and the liquid LQ may bemeasured (analyzed) by using a measuring device (analyzer) providedseparately from the exposure apparatus EX. Moreover, when fineparticles, bubbles, or dissolved oxygen are to be measured, the liquidLQ may be sampled at a predetermined timing, and the liquid LQ may bemeasured by using the measuring device provided separately from theexposure apparatus EX. Alternatively, in the embodiment shown in FIG. 2,for example, a valve may be provided for each of the branch pipes 61K to63K, and the valve may be operated to allow the liquid LQ flowing in thesupply pipe 13 to flow into the measuring device 60 at a predeterminedtiming, so as to measure the liquid LQ intermittently. On the otherhand, measurement by the measuring device 60 can be stabilized bysupplying the liquid LQ flowing in the supply pipe 13 to the measuringdevice 60 all the time to measure the liquid continuously.

In the embodiment, the branch pipes 61K, 62K, 63K, and 64K are connectedto the connection pipe 13 between the liquid supply device 11 and thefirst nozzle member 70, and the measuring device 60 measures the liquidLQ branched from the supply pipe 13. In this case, it is desired thatthe branch pipes are provided as close as possible to the first nozzlemember 70 (the supply outlet 12).

In the embodiment, the branch pipes 61K, 62K, 63K, and 64K function assampling ports for sampling the liquid LQ flowing in the supply pipe 13,and the measuring device 60 measures the liquid LQ sampled by using thebranch channel provided somewhere in the supply pipe 13 between thetemperature controller 17 and the first nozzle member 70. However, thesampling port may be fitted to, for example, near the supply outlet 12of the first nozzle member 70, so that the measuring device 60 measuresthe liquid LQ flowing near the supply outlet 12. The sampling port maybe provided between the pure water production device 16 and thetemperature controller 17, immediately after the temperature controller17 on the downstream side, or the sampling port may be provided in theconnection pipe 9, so that the measuring device 60 measures the liquidLQ flowing in the connection pipe 9.

Moreover, as shown in FIG. 7, the measuring device 60′ may measure theliquid LQ recovered by the first liquid recovery mechanism 20. In FIG.7, a meter 65 of the measuring device 60′ is connected to a branch pipe65K branched from somewhere along the recovery pipe 23 of the firstliquid recovery mechanism 20. That is, in the example shown in FIG. 7,the sampling port of the measuring device 60′ is provided in therecovery pipe 23. The meter 65 measures the liquid LQ coming in contactwith the substrate P. There is a possibility that the liquid LQ comingin contact with the substrate P may contain eluates from a protectionfilm referred to as a photoresist of a top coat provided on thesubstrate P. The meter 65 can measure the property and composition ofthe liquid LQ containing these eluates. Furthermore, the controller CONTcan store the measurement result of the meter 65 in correspondence withthe time course or the shot area in the storage device MRY as loginformation.

For example, the controller CONT can determine a change amount of theeluates with the lapse of time based on the log information. When thechange amount considerably increases with the lapse of time, it can bedetermined that the photoresist is soluble relative to the liquid LQ.Furthermore, the controller CONT can determine acidity of the recoveredliquid LQ. The liquid LQ having high acidity causes corrosion (rust) ofmembers coming in contact with the liquid LQ, such as the recovery pipe23. Therefore, the controller CONT informs a measurement result (loginformation) of the property or composition of the recovered liquid LQ,for example, by the notifying device INF, so as to take a measure suchas urging review (change) of the type of the photoresist to be used.

Since the meter 65 measures the liquid LQ via the porous body 22Pprovided in the first collection inlet 22, impurities (live bacteria andthe like) adhering to the porous body 22P and the recovery pipe 23 canbe measured. When the liquid immersion exposure process is performed ina state with the impurities adhering to the porous body 22P or the like,the impurities adhering to the porous body 22P are mixed in the liquidimmersion area AR2 formed on the substrate P, whereby the exposureaccuracy may deteriorate. Therefore, the controller CONT informs themeasurement result (log information) of the property or composition ofthe recovered liquid LQ, for example, by the notifying device INF, so asto take a measure such as urging replacement or cleaning of the porousbody 22P.

As shown in FIG. 7, a measuring device 60″ may be provided on thesubstrate stage PST. In FIG. 7, the measuring device 60″ includes ameter 66 embedded in the substrate stage PST, and a sampling port (hole)67 provided on the upper face 51 of the substrate stage PST. When themeter 66 measures the liquid LQ, the liquid immersion area AR2 of theliquid LQ is formed on the image surface side of the projection opticalsystem PL, the liquid immersion area AR2 and the substrate stage PST arerelatively moved so as to arrange the liquid immersion area AR2 abovethe sampling port 67, and the liquid LQ is allowed to flow to thesampling port 67. The meter 66 measures the liquid LQ obtained via thesampling port 67.

The controller CONT can supply a functional liquid LK from the liquidsupply mechanism 10 to respective members coming in contact with theliquid LQ forming the liquid immersion area AR2, to clean these members.For example, if the liquid LQ is not in a desired state but iscontaminated, for example, lots of live bacteria are contained in theliquid LQ, there is a possibility of contaminating the respectivemembers coming in contact with the liquid LQ, specifically, the liquidcontact face 70A of the first nozzle member 70, the liquid contact face80A of the second nozzle member 80, the supply channel 14 and the firstrecovery channel 24 as inner channels of the first nozzle member 70, thesecond recovery channel 34 as the inner channel of the second nozzlemember 80, the supply pipe 13 as a channel forming member coming incontact with the first nozzle member 70, the recovery pipe 33 connectedto the second nozzle member 80, the liquid contact face 2A of theoptical element 2, the upper face 51 of the substrate stage PST, and themeasuring member 300 and the light measuring devices 400, 500, and 600on the substrate stage PST. If these members are contaminated, even ifthe clean liquid LQ is supplied from the liquid supply device 11, theliquid LQ is contaminated due to the contact with these members, and ifthe liquid immersion area AR2 is formed by the contaminated liquid LQ,the exposure accuracy and the measurement accuracy via the liquid LQdeteriorate.

Therefore, for example, when the quantity of the live bacteria is largerthan the tolerance based on the measurement result of the measuringdevice 60, the controller CONT supplies a functional liquid LK having abactericidal action to the above described respective members from thefunctional liquid supply device (cleaning device) 120 constituting apart of the liquid supply mechanism 10, to thereby clean the respectivemembers.

In the embodiment, in order to remove the live bacteria of the memberscoming in contact with the liquid, the functional liquid supply device120 supplies the functional liquid LK having the bactericidal action. Asthe functional liquid LK having the bactericidal action, for example,hydrogen peroxide solution or liquid containing ozone can be mentioned.

A maintenance method using the functional liquid LK will be describedbelow with reference to FIG. 8. At the time of cleaning the members, thecontroller CONT drives the valve 19B provided in the supply pipe 19connecting the functional liquid supply device 120 and the liquid supplydevice 11, to open the flow channel of the supply pipe 19, and closesthe flow channel of the return pipe 18 by the valve 18B. By this action,the functional liquid LK having the bactericidal action is supplied fromthe functional liquid supply device 120 to the liquid supply device 11(step SB1). The functional liquid LK supplied from the functional liquidsupply device 120 flows in the liquid supply device 11 including thepure water production device 16 and the temperature controller 17, thenflows in the supply pipe 13 and the supply channel 14 of the firstnozzle member 70, and is supplied to the image surface side of theprojection optical system PL via the supply outlet 12. The functionalliquid supply device 120 supplies the functional liquid LK to the flowchannels (the supply pipe 13, the supply channel 14, and the like)constituting the liquid supply mechanism 10, through which the liquid LQflows, to thereby clean these flow channels. However, when there is amember, which cannot allow the functional liquid LK to flow, in the flowchannel, the member needs to be removed beforehand. Specifically, sincethe ion exchange membrane mounted on the pure water production unit 161will be broken if the hydrogen peroxide solution passes therethrough,the ion exchange membrane is removed beforehand. The controller CONTinstructs to remove the ion exchange membrane by the notifying deviceINF before driving the valve 19B.

When the functional liquid supply device 120 is supplying the functionalliquid LK to the image surface side of the projection optical system PL,a dummy substrate is held on the substrate stage PST (the substrateholder PH). The dummy substrate has substantially the same size andshape as those of the substrate P for device production. In theembodiment, the dummy substrate has liquid repellency with respect tothe functional liquid LK. The dummy substrate need not have liquidrepellency with respect to the functional liquid LK. The functionalliquid LK fed from the functional liquid supply device 120 is suppliedonto the dummy substrate from the supply outlet 12, to form the liquidimmersion area on the image surface side of the projection opticalsystem PL. When the functional liquid supply device 120 is supplying thefunctional liquid LK, the first liquid recovery mechanism 20 and thesecond liquid recovery mechanism 30 are performing the liquid recoveryoperation (suction operation), similar to at the time of the liquidimmersion exposure operation. Therefore, the functional liquid LK in theliquid immersion area formed on the image surface side of the projectionoptical system PL is recovered via the first collection inlet 22, flowsin the first recovery channel 24 and the recovery pipe 23, and is thenrecovered by the first liquid recovery device 21. The controller CONTincreases the supply amount of the functional liquid per unit time fromthe functional liquid supply device 120, or decreases the recoveryamount of the functional liquid per unit time by the first liquidrecovery mechanism 20, to thereby increase the liquid immersion area ofthe functional liquid LK, and the functional liquid LK in the liquidimmersion area is recovered via the second collection inlet 32 of thesecond liquid recovery mechanism 30. By doing this, the functionalliquid LK recovered via the second collection inlet 32 flows in thesecond recovery channel 34 and the recovery pipe 33, and is recovered bythe second liquid recovery device 31. Thus, since the functional liquidLK flows in the flow channels of the first and the second liquidrecovery mechanisms 20 and 30, these flow channels are cleaned.Moreover, the functional liquid LK recovered via the first and thesecond collection inlets 22 and 33 may be recovered by another recoverydevice separate from the first and the second liquid recovery devices 21and 31, instead of being recovered by the first and the second liquidrecovery devices 21 and 31. The recovered functional liquid LK may bereturned to the liquid supply device 11 again, or may be disposed of.Thus, the liquid LQ is replaced by the functional liquid LK (step SB2).

The functional liquid LK in the liquid immersion area formed on theimage surface side of the projection optical system PL also comes incontact with the liquid contact face 2A of the optical element 2 and theliquid contact faces 70A and 80A of the nozzle members 70 and 80, andhence, these liquid contact faces 2A, 70A and 80A can be cleaned.Moreover, by two-dimensionally moving the substrate stage PST in the XYdirections relative to the liquid immersion area, in a state with theliquid immersion area of the functional liquid LK being formed, theupper face 51 of the substrate stage PST, the measuring member 300, andthe light measuring devices 400, 500, and 600 provided on the substratestage PST can be cleaned (step SB3).

Thus, by performing the liquid immersion area-forming operation of thefunctional liquid LK in the same procedure as at the time of the liquidimmersion exposure operation, the respective members can be efficientlycleaned simultaneously.

As the cleaning procedure using the functional liquid LK, after thefunctional liquid LK is supplied from the functional liquid supplydevice 120, supply and recovery operations of the functional liquid LKare continued for a predetermined time in the same procedure as at thetime of the liquid immersion exposure operation, to thereby form theliquid immersion area of the functional liquid LK on the image surfaceside of the projection optical system PL. After heating the functionalliquid LK, the functional liquid LK may be allowed to flow to the liquidsupply mechanism 10 and the flow channels of the first and the secondliquid recovery mechanisms 20 and 30. After a predetermined time haspassed, the supply and recovery operations of the functional liquid LKare stopped. In this state, the functional liquid LK is held on theimage surface side of the projection optical system PL, to form animmersion state. After the immersion state is maintained for apredetermined time, the controller CONT operates the valves 19B and 18Bagain to switch the piping channels, so as to supply the liquid LQ fromthe liquid supply device 11 to the supply pipe 13 (step SB4). The supplyand recovery operations of the liquid LQ (for example, pure water) areperformed for a predetermined time by the liquid supply mechanism 10 andthe first and the second liquid recovery mechanisms 20 and 30, tothereby form the liquid immersion area of the liquid LQ on the imagesurface side of the projection optical system PL. As a result, theliquid LQ flows in respective flow channels of the liquid supplymechanism 10, the first liquid recovery mechanism 20, and the secondliquid recovery mechanism 30, and the functional liquid LK remaining inthe flow channels is washed away by the liquid LQ (step SB5). Moreover,the liquid contact face 2A of the optical element 2 and the liquidcontact faces 70A and 80A of the nozzle members 70 and the second nozzlemember 80 are also cleaned by the liquid immersion area of the purewater. At this time, since the substrate stage PST moves in the statewith the liquid immersion area of the liquid LQ being formed, thefunctional liquid LK remaining on the upper face 51 of the substratestage PST, the measuring member 300, and the light measuring devices400, 500, and 600, with which the functional liquid LK has come incontact, are washed away by the liquid LQ.

After the cleaning process has finished, the liquid LQ is measured bythe measuring device 60, whereby it can be confirmed whether thecleaning process has been performed satisfactorily, that is, whether theliquid LQ is in the desired state.

In the embodiment, the upper face 51 of the substrate stage PST hasliquid repellency in order to suppress the outflow of the liquid LQ tothe outside of the substrate P (outside of the upper face 51) duringliquid immersion exposure, and to prevent an undesirable situation wherethe liquid LQ can be smoothly recovered after the liquid immersionexposure and the liquid LQ remains on the upper face 51. The upper face51 is formed of a material having liquid repellency such aspolytetrafluoroethylene (Teflon®). The upper face 51 may be madeliquid-repellent by performing liquid-repellent processing, for example,applying a liquid-repellent material, such as a fluororesin materialsuch as polytetrafluoroethylene, an acrylic resin material, or a siliconresin material, or by affixing a thin film formed of the aboveliquid-repellent materials.

The optical element 2 is formed of fluorite or quartz and the liquidcontact face 2A of the optical element 2 has a lyophilic property.Moreover, the liquid contact face 70A of the first nozzle member 70 (andthe liquid contact face 80A of the second nozzle member 80 according tocircumstances) also has the lyophilic property. Since these liquidcontact faces have the lyophilic property, the liquid can besatisfactorily held on the image surface side of the projection opticalsystem PL, thereby forming the liquid immersion area. When lyophilicprocessing is performed with respect to the liquid contact faces 2A and70A to make these faces lyophilic, for example, lyophilic materials suchas MgF₂, Al₂O₃, or SiO₂ can be adhered (applied) thereto. Since theliquid LQ in the embodiment is water having large polarity, by forming athin film with a material having a large molecular structure such asalcohol as the lyophilic processing (hydrophilic processing), ahydrophilic property can be given. It is desired that the functionalliquid LK is formed of a material, which does not affect these liquidcontact faces.

It is also desired that the functional liquid LK is formed of a materialwhich does not affect the upper face 51 of the substrate stage PST andthe liquid contact faces 2A, 70A, and 80A. When the upper face 51 of thesubstrate stage PST and the like are formed of a material having notolerance with respect to the functional liquid LK having thebactericidal action, the liquid immersion area of the functional liquidLK can be formed on the image surface side of the projection opticalsystem PL, in a state with the dummy substrate covering the whole areaof the upper face 51 of the substrate stage PST, mounted on thesubstrate stage PST.

In the above embodiments, it is described that the operation of theliquid supply mechanism 10 including the functional liquid supply device120 is controlled based on the measurement result of the measuringdevice 60, to perform the cleaning process. However, it is of coursepossible to have such a configuration that the cleaning process isperformed, for example, at intervals of predetermined time (for example,every month, or every year), without depending on the measurement resultof the measuring device 60. As a contamination source which contaminatesthe members coming in contact with the liquid LQ (the first nozzlemember 70, the optical element 2, and the like), not only thecontaminated liquid LQ, but also impurities floating in the air mayadhere to these members, thereby contaminating the members. Even in sucha case, by performing the cleaning process at intervals of predeterminedtime without depending on the measurement result of the measuring device60, contamination of the members, and contamination of the liquid LQcoming contact with the members can be prevented.

In the above embodiments, a cleaning liquid having a bactericidal action(sterilizing function) is supplied as the functional liquid LK, however,foreign matter adhering to the members including the supply pipe 13 andthe recovery pipe 23 can be removed by flushing hydrogen water as thefunctional liquid LK. By flushing the functional liquid (hydrogen water)having a foreign matter-removing function to remove the foreign matterat the time of the cleaning process, an undesirable situation where theforeign matter is mixed in the liquid immersion area AR2 can beprevented at the time of liquid immersion exposure. Moreover, byflushing carbon dioxide water as the functional liquid, electricalconductivity of the member including the supply pipe 13 and the recoverypipe 23 can be controlled. By flushing the functional liquid (carbondioxide water) having a function of controlling the electricalconductivity, generation of static electricity from the members can beprevented, and charged members can be discharged. As a result,occurrence of defective exposure operation due to generation of staticelectricity (electrical noise) and breakdown due to static electricityof the pattern resulting from electrical discharge can be prevented.

In the above embodiments, the process for flushing the functional liquidLK (cleaning process) and the liquid immersion exposure process areexecuted separately. However, if the functional liquid LK can be used asthe liquid for the liquid immersion exposure, the liquid immersion areaAR2 for performing liquid immersion exposure can be formed by thefunctional liquid LK. In this case, the cleaning process and the liquidimmersion exposure process are performed simultaneously.

In the above embodiments, the functional liquid supply device 120supplies the functional liquid LK to the pure water production device16. However, the configuration may be such that the functional liquidsupply device 120 is connected to between the pure water productiondevice 16 and the temperature controller 17, and a valve for preventingthe functional liquid LK from flowing backward to the pure waterproduction device 16 is provided, so as to supply the functional liquidLK to the downstream of the temperature controller 17. According to thisconfiguration, at the time of supplying the functional liquid LK, theion exchange membrane of the pure water production device 16 need not beremoved.

The liquid LQ in the above embodiments is constituted by pure water.Pure water has the advantage that it is easily available in bulk in,e.g., semiconductor manufacturing factories and also the advantage thatit does not adversely affect photoresist on the substrate P, opticalelements (lenses), etc. Further, pure water does not adversely affectthe environment and contains scarcely any impurities; thus, the effectthat it cleans the surface of the substrate P and the surface of theoptical element provided at the end portion of projection optical systemPL can be expected. When the purity of the pure water supplied from thefactories or the like is low, the exposure apparatus may include anultra-pure water production device.

It is generally said that the refractive index n of pure water (water)relative to the exposure light EL having a wavelength of about 193 nm isapproximately 1.44, and thus when the ArF excimer laser light(wavelength of 193 nm) is used as the light source of the exposure lightEL, the wavelength of the exposure light is effectively shortened, onthe substrate P, as if multiplied by 1/n, i.e., effectively becomesapproximately 134 nm, and thus, a high resolution can be obtained.Further, since the depth of focus increases by approximately n times,i.e., approximately by 1.44 times, compared with that in the air, whensecuring of the depth of focus on par with the depth of focus realizedwhen the projection optical system is used in the air suffices, thenumerical aperture of the projection optical system PL can be furtherincreased; which also improves the resolution.

When the liquid immersion method is used as described above, thenumerical aperture NA of the projection optical system PL may become 0.9to 1.3. When the numerical aperture NA of the projection optical systemPL becomes large, random-polarized light conventionally used as theexposure light may, because of its polarization effect, adversely affectthe imaging performance; thus, a polarized light illumination method ispreferably used. In this case, it is preferable that by performinglinearly polarized light illumination in which the longitudinaldirection of the line pattern of the line-and-space pattern on the mask(reticle) is aligned with the polarization direction, S polarizationcomponents (TE polarization components), that is, diffracted lights ofthe polarization components having the polarization direction in linewith the longitudinal direction of the line pattern are emitted in largequantities from the pattern of the mask (reticle). When the spacebetween the projection optical system PL and the resist applied to thesurface of the substrate P is filled with the liquid, the transmittanceat the resist surface of the diffracted lights from S polarizationcomponents (TE polarization components), which contribute to theimprovement of the contrast, is higher compared with the case where thespace between the projection optical system PL and the resist applied tothe surface of the substrate P is filled with the air (gas). Therefore ahigh imaging performance can be obtained even in the case where thenumerical aperture NA of the projection optical system is over 1.0. Whena phase shift mask and an oblique-incidence illumination system(particularly, a dipole illumination system) matched with thelongitudinal direction of the line pattern, as disclosed in JapaneseUnexamined Patent Application, First Publication No. H06-188169, and thelike are appropriately combined, it works more effectively. Thecombination of the linearly polarized light illumination system and thedipole illumination system is particularly effective, when the periodicdirection of the line-and-space pattern is limited to a predeterminedone direction, or when the hole patterns are overcrowded along apredetermined one direction. For example, when a halftone-type phaseshift mask (a pattern having a half pitch of about 45 nm) having atransmittance of 6% is illuminated by using both the linearly polarizedlight illumination system and the dipole illumination system, if it isassumed that illumination σ regulated by a two-beam circumcircle forminga dipole on a pupil plane of the illumination system is 0.95, a radiusof respective beams on the pupil plane is 0.125 σ, and the numericalaperture NA of the projection optical system PL is 1.2, the depth offocus (DOF) can be increased by about 150 nm, more than for a case ofusing random-polarized light.

For example, when the ArF excimer laser light is used as the exposurelight, and a fine line-and-space pattern (for example, line-and-space ofabout 25 to 50 nm) is exposed on the substrate P by using the projectionoptical system PL having a reduction magnification of about ¼, the maskM acts as a polarizing plate due to a wave guide effect depending on thestructure of the mask M (for example, fineness of the pattern andthickness of chrome), and hence, the diffracted lights from the Spolarization components (TE polarization components) are emitted fromthe mask M in larger quantities than the diffracted light from Ppolarization components (TM polarization components), which decreasescontrast. In this case, it is desired to use the linearly polarizedlight illumination, however, even by illuminating the mask M by therandom-polarized light, high resolution performance can be obtained,even when the numerical aperture NA of the projection optical system PLis as large as 0.9 to 1.3.

When an extra fine line-and-space pattern on the mask M is exposed onthe substrate P, there is a possibility that the P polarizationcomponents (TM polarization components) increases more than the Spolarization components (TE polarization components) due to a wire grideffect. However, for example, when the ArF excimer laser light is usedas the exposure light, and a line-and-space pattern larger than 25 nm isexposed on the substrate P by using the projection optical system PLhaving a reduction magnification of about ¼, the diffracted lights fromthe S polarization components (TE polarization components) are emittedfrom the mask M in larger quantities than the diffracted light from Ppolarization components (TM polarization components). As a result, highresolution performance can be obtained, even when the numerical apertureNA of the projection optical system PL is as large as 0.9 to 1.3.

Moreover, not only the linearly polarized light illumination (Spolarized light illumination) matched with the longitudinal direction ofthe line pattern of the mask (reticle), but also as disclosed inJapanese Unexamined Patent Application, First Publication No. H06-53120,a combination of a polarized light illumination system which linearlypolarizes in a tangential (circumferential) direction of a circlecentering on the optical axis and the oblique-incidence illuminationsystem are effective. Particularly, when a line pattern in which thepattern of the mask (reticle) extends in a predetermined one directionand a line pattern extending in a plurality of different directions areintermingled (a line-and-space pattern having a different periodicdirection is intermingled), then as disclosed in Japanese UnexaminedPatent Application, First Publication No. H06-53120, by using thepolarized light illumination system which linearly polarizes in thetangential direction of the circle centering on the optical axis and anannular illumination system together, high imaging performance can beobtained, even when the numerical aperture NA of the projection opticalsystem is large. For example, when the halftone-type phase shift mask (apattern having a half pitch of about 63 nm) having a transmittance of 6%is illuminated by using both the polarized light illumination systemwhich linearly polarizes in the tangential direction of the circlecentering on the optical axis and the annular illumination system (zoneratio: ¾), if it is assumed that illumination C is 0.95 and thenumerical aperture NA of the projection optical system PL is 1.0, thedepth of focus (DOF) can be increased by about 250 nm, more than for acase of using the random-polarized light. In the case of a patternhaving a half pitch of about 55 nm and the numerical aperture NA of theprojection optical system PL being 1.2, the depth of focus (DOF) can beincreased by about 100 nm.

In the above embodiments, the optical element (lens) 2 is attached tothe end of the projection optical system PL, and with the aid of thislens, the optical characteristics of the projection optical system PL,for example, aberration (spherical aberration, coma aberration, etc.)can be adjusted. In the above respective embodiments, the configurationis such that the optical path space on the emission side of the opticalelement 2 of the projection optical system PL is filled with the liquidLQ to expose the substrate P. However, as disclosed in PCT InternationalPublication No. WO 2004/019128, both of the optical path space on theincident side and the optical path space on the emission side of opticalelement 2 of the projection optical system PL may be filled with theliquid LQ. In this case, a part or all of the matters described in theabove embodiments may be applied to the liquid LQ to be filled in theoptical path space on the incident side of the optical element 2. Forexample, the property or composition of the liquid LQ to be supplied tothe incident side of the optical element 2 can be controlled as in theliquid LQ to be supplied to the emission side. Alternatively, a controlvalue of the property or composition of the liquid LQ is made differentbetween the incident side and the emission side of the optical element2, taking into consideration a difference of influence on the exposureperformance, so as to control the property or composition of the liquidLQ independently. The functional liquid LK may be introduced also to theincident side of the optical element 2, so as to perform cleaning anddischarge. As the optical element to be attached to the end of theprojection optical system PL, an optical plate used for the adjustmentof the optical characteristics of the projection optical system PL maybe utilized. Alternatively, a plane parallel plate that can transmitexposure light EL may be utilized.

If the pressure, caused by the flow of the liquid LQ, of the spacebetween the optical element located at the end of the projection opticalsystem PL and the substrate P is high, the optical element may berigidly fixed so as not to move due to the pressure, instead of makingthe optical element replaceable.

In the embodiments, the configuration is such that the space between theprojection optical system PL and the surface of the substrate P isfilled with the liquid LQ, however the configuration may also be, forexample, such that the space is filled with the liquid LQ in the statethat a cover glass constituted by a plane parallel plate is attached tothe surface of the substrate P

In the embodiments, the liquid LQ is water, but the liquid LQ may be aliquid other than water. For example, when the light source of theexposure light EL is an F₂ laser, the F₂ laser light does not transmitthrough water, and thus, as the liquid LQ, a fluorofluid that cantransmit the F₂ laser light, such as perfluoropolyether (PFPE) orfluorochemical oil, may be used. In this case, a thin film is formed ona portion coming in contact with liquid LQ with a material having amolecular structure having small polarity, for example, containingfluorine, to perform lyophilic processing. Further, as the liquid LQ, amaterial (e.g., cedar oil) that can transmit the exposure light EL, hasa high refractive index as high as practicable, and does not affect theprojection optical system PL and the photoresist applied to the surfaceof substrate P can also be used. Also in this case, the surfacetreatment is applied in accordance with the polarity of the liquid LQ tobe used.

As for the substrate P of each of the above-described embodiments, notonly a semiconductor wafer for manufacturing a semiconductor device, butalso a glass substrate for a display device, a ceramic wafer for a thinfilm magnetic head, a master mask or reticle (synthetic quartz orsilicon wafer), etc. used in the exposure apparatus can be used.

As for the exposure apparatus EX, in addition to a scan type exposureapparatus (scanning stepper) of a step-and-scan method in which whilesynchronously moving the mask M and the substrate P, the pattern of themask M is scan-exposed, a step-and-repeat type projection exposureapparatus (stepper) in which the pattern of the mask M is exposed in abatch in the state with the mask M and the substrate P being stationary,and the substrate P is successively moved stepwise can be used.

Moreover, as for the exposure apparatus EX, the present invention can beapplied to an exposure apparatus EX of a method in which a reduced imageof a first pattern is exposed in a batch on the substrate P by using theprojection optical system (for example, a refractive projection opticalsystem having, for example, a reduction magnification of ⅛, which doesnot include a reflecting element), in the state with the first patternand the substrate P being substantially stationary. In this case, thepresent invention can be also applied to a stitch type batch exposureapparatus in which after the reduced image of the first pattern isexposed in a batch, a reduced image of a second pattern is exposed in abatch on the substrate P, partially overlapped on the first pattern byusing the projection optical system, in the state with the secondpattern and the substrate P being substantially stationary. As thestitch type exposure apparatus, a step-and-stitch type exposureapparatus in which at least two patterns are transferred onto thesubstrate P in a partially overlapping manner, and the substrate P issequentially moved, can be used.

Further, the present invention can be applied to a twin stage typeexposure apparatus as disclosed in Japanese Unexamined PatentApplication, First Publication No. H10-163099, Japanese UnexaminedPatent Application, First Publication No. H10-214783, and PublishedJapanese Translation No. 2000-505958 of PCT International Application.

In the above embodiments, an exposure apparatus in which the liquid islocally filled in the space between the projection optical system PL andthe substrate P is used. However, the present invention can be alsoapplied to a liquid immersion exposure apparatus in which a stageholding a substrate to be exposed is moved in a liquid tank, asdisclosed in Japanese Unexamined Patent Application, First PublicationNo. H06-124873.

As the type of the exposure apparatus EX, the present invention is notlimited to an exposure apparatus which exposes a semiconductor patternonto the substrate P, for manufacturing semiconductor devices, but canalso be applied to a variety of exposure apparatuses, e.g., an exposureapparatus for manufacturing liquid crystal display devices or displays,an exposure apparatus for manufacturing thin film magnetic heads, and anexposure apparatus for manufacturing image pickup devices (CCD),reticles or masks.

When using a linear motor (see U.S. Pat. No. 5,623,853 or U.S. Pat. No.5,528,118) for the substrate stage PST and/or the mask stage MST, eitherair-floating type linear motor using an air bearing, or a magneticlevitation type linear motor using a Lorentz force or reactance forcemay be used. Further, each of the substrate stage PST and the mask stageMST may be either of a type moving along a guide, or of a guideless typehaving no guide.

As for the driving mechanism for each of the substrate stage PST and themask stage MST, a planar motor in which by making a magnet unit in whichmagnets are two-dimensionally arranged and an armature unit in whichcoils are two-dimensionally arranged face each other, each of thesubstrate stage PST and the mask stage MST is driven by anelectromagnetic force, may be used. In this case, either one of themagnet unit and the armature unit is attached to the stage PST and thestage MST, and the other unit is attached to the moving surface side ofthe stage PST or the stage MST A reaction force generated by themovement of the substrate stage PST may be, as described in JapaneseUnexamined Patent Application, First Publication No. H08-166475 (U.S.Pat. No. 5,528,118), mechanically released to the floor (earth) by useof a frame member so that the force does not transmit to the projectionoptical system PL.

A reaction force generated by the movement of the mask stage MST may be,as described in Japanese Unexamined Patent Application, FirstPublication No. H08-330224 (U.S. patent application Ser. No.08/416,558), mechanically released to the floor (earth) by use of aframe member so that the force does not transmit to the projectionoptical system PL.

The exposure apparatus EX according to the embodiments of the presentapplication is built by assembling various subsystems, including eachelement listed in the claims of the present application, in such amanner that prescribed mechanical accuracy, electrical accuracy, andoptical accuracy are maintained. In order to ensure the variousaccuracies, prior to and after the assembly, every optical system isadjusted to achieve its optical accuracy, every mechanical system isadjusted to achieve its mechanical accuracy, and every electrical systemis adjusted to achieve its electrical accuracy.

The process of assembling each subsystem into the exposure apparatusincludes mechanical interfaces, electrical circuit wiring connections,and air pressure plumbing connections between each subsystem. Needlessto say, there is also a process where each subsystem is assembled priorto the assembling of the exposure apparatus from the various subsystems.On completion of the process of assembling the various subsystems in theexposure apparatus, overall adjustment is performed to make sure thatthe above accuracies are maintained in the complete exposure apparatus.Additionally, it is desirable to manufacture the exposure apparatus in aclean room, in which the temperature, purity, etc. are controlled.

As shown in FIG. 9, micro devices such as semiconductor devices aremanufactured by a series of steps, including: a step 201 in which themicro device's function and performance design is performed; a step 202in which a mask (reticle) is manufactured based on the design step; astep 203 in which a substrate, the device's base material, ismanufactured; a substrate process step 204 in which the mask pattern isexposed onto the substrate by the exposure apparatus EX according to theabove-described embodiments; a device assembly step 205 (including thedicing process, bonding process, and packaging process); and aninspection step 206.

1-33. (canceled)
 34. A method for preventing or reducing contaminationof an immersion type projection apparatus, the apparatus comprising atleast one immersion space that is at least partially filled with aliquid when the apparatus projects a beam of radiation onto a substrate,the method comprising: rinsing at least part of the immersion space witha rinsing liquid before the apparatus is used to project the beam ofradiation onto a substrate.
 35. A method according to claim 34, whereinthe rinsing of the immersion space occurs during an idle operationalmode of the apparatus.
 36. A method according to claim 34, wherein saidliquid and said rinsing liquid are the same liquid.
 37. A methodaccording to claim 34, wherein the rinsing of the immersion space occurssubstantially continuously until the apparatus is used to projectradiation onto a substrate.
 38. A method according to claim 34, furthercomprising illuminating at least part of the immersion space and/or therinsing liquid with ultraviolet radiation.
 39. A method according toclaim 34, wherein said immersion space at least extends between at leastpart of a substrate, a dummy substrate or a substrate-shaped objectand/or a substrate holder on one side, and a projection system on anopposite side.
 40. A method according to claim 39, further comprising:placing the dummy substrate or the substrate-shaped object on saidsubstrate holder; and replacing the dummy substrate or thesubstrate-shaped object a substrate to be illuminated by the projectionsystem after the rinsing has been completed.
 41. A method according toclaim 34, wherein said immersion space at least extends between apatterning device, a dummy patterning device or a patterningdevice-shaped object and/or a patterning device holder on one side, anda projection system on opposite side.
 42. A method according to claim41, further comprising: placing the dummy patterning device or thepatterning device-shaped object on said patterning device holder; andreplacing the dummy patterning device or the patterning device-shapedobject with a patterning device to be used to pattern radiation beforethe radiation enters the projection system.
 43. A method according toclaim 34, wherein the apparatus is a lithographic projection apparatus.44. A method according to claim 34, further comprising: varying thelocation of the immersion space during the rinsing of the immersionspace to clean different parts and/or areas of the apparatus.
 45. Amethod for preventing or reducing contamination of a lithographicprojection apparatus, the apparatus including a substrate holderconstructed to hold a substrate, a patterning device holder constructedto hold a patterning device, a projection system, and an immersionsystem configured to at least partially fill an immersion space of theapparatus with a liquid, the method comprising: moving at least one ofthe immersion system and at least part of the apparatus relative to eachother; and rinsing said at least part of the apparatus with the liquidbefore the apparatus is used to project a patterned beam of radiationonto a target portion of a substrate.
 46. A method according to claim45, wherein said at least part of the apparatus comprises at least partof the substrate holder.
 47. A method according to claim 45, whereinsaid at least part of the apparatus comprises at least one slit oraperture extending in or near the substrate holder.
 48. A methodaccording to claim 45, wherein said at least part of the apparatuscomprises at least part of the patterning device holder.
 49. A methodaccording to claim 45, wherein said at least part of the apparatuscomprises at least one slit or aperture extending in or near thepatterning device holder.
 50. A method for preventing or reducingcontamination of a lithographic projection apparatus, the apparatusincluding an immersion space, the method comprising: filling at leastpart of the immersion space with a rinsing liquid for at least oneminute.
 51. A method according to claim 50, wherein the filling occurssubstantially continuously for at least one day, including at least oneidle operational period of the apparatus or a part thereof.
 52. A methodfor preventing or reducing contamination of a lithographic projectionapparatus, the apparatus including a substrate holder constructed tohold a substrate, a patterning device holder constructed to hold apatterning device, a projection system, and an immersion space, themethod comprising: filling at least part of the immersion space with arinsing liquid during an idle time of the apparatus to prevent or reducesubstrate contamination during at least one subsequent start-up run ofthe apparatus.
 53. A method according to claim 52, wherein the rinsingliquid consists of ultra pure water.
 54. An immersion type lithographicapparatus comprising: at least one immersion space; and an immersionsystem configured to at least partially fill the immersion space with aliquid, wherein the apparatus is configured to rinse at least part ofthe immersion space with a rinsing liquid before the apparatus is usedto project a patterned beam of radiation onto a substrate.
 55. Anapparatus according to claim 54, wherein the apparatus is configured torinse at least part of the immersion space during an idle operationalmode of the apparatus.
 56. An apparatus according to claim 54, whereinthe apparatus is configured to provide an object in said immersion spaceand/or in an adjoining position with respect to the immersion spaceduring the rinsing of that space, and to remove said object before theapparatus is used to project a radiation beam onto a target portion of asubstrate.
 57. An apparatus according to claim 56, further comprising atleast one storage space or compartment to store said object when theapparatus is used to project a radiation beam onto a target portion ofthe substrate.
 58. An apparatus according to claim 54, wherein theapparatus is configured to rinse the immersion space with said liquid.59. An apparatus according to claim 54, wherein the apparatus isconfigured to rinse the immersion space substantially continuously untilthe apparatus projects a radiation beam onto a substrate.
 60. Anapparatus according to claim 54, further comprising at least one ultraviolet radiation source configured to illuminate the immersion spacewith ultraviolet radiation during the rinsing of that space, before theapparatus is used to project a radiation beam onto a target portion of asubstrate.
 61. An apparatus according to claim 54, wherein saidimmersion space extends between at least part of a substrate, a dummysubstrate, a substrate-shaped object and/or a substrate holder on oneside and part of a projection system of the apparatus on an oppositeside.
 62. An apparatus according to claim 61, wherein the apparatus isconfigured to place the dummy substrate or the substrate-shaped objecton said substrate holder, and to subsequently rinse the respectiveimmersion space.
 63. An apparatus according to claim 61, wherein saidapparatus is configured to have the immersion space at least reach orinclude an outer contour of the substrate, the dummy substrate or thesubstrate-shaped object, being held by said substrate holder, during therinsing.
 64. An apparatus according to claim 54, wherein the apparatusis configured to rinse at least an area extending along an edge of asubstrate, a dummy substrate or a substrate-shaped object, being held bya substrate holder, using said immersion space and said rinsing liquid.65. An apparatus according to claim 54, wherein the apparatus isconfigured to rinse at least part of a surface of the substrate holderand/or one or more components that are located on that surface usingsaid immersion space and said rinsing liquid.
 66. An apparatus accordingto claim 65, wherein said components are selected from the groupconsisting of an edge seal member, a sensor, a positioning device, and amirror element.
 67. An apparatus according to claim 54, furthercomprising at least two substrate holders, wherein said immersion spaceextends between at least part of at least one of the substrate holderson one side and a projection system on an opposite side, and wherein theapparatus is configured to move each substrate holder to a firstposition and to a respective second position, away from said projectionsystem.
 68. An apparatus according to claim 67, wherein the apparatus isconfigured to subsequently move said substrate holders to said firstposition, to be at least partially rinsed in or near that position bysaid rinsing liquid.
 69. An apparatus according to claim 67, furthercomprising at least one cleaning device configured to at least partiallyclean at least one of the substrate holders when that substrate holderis in said second position.
 70. An apparatus according to claim 67,wherein the apparatus is configured to determine which of said substrateholders is most likely to be contaminated and to rinse or clean thesubstrate holder that has been found to be most likely contaminated,first.
 71. An apparatus according to claim 54, wherein said immersionspace at least extends between a patterning device and/or patterningdevice holder on one side and a projection system on an opposite side.72. An apparatus according to claim 71, wherein the apparatus isconfigured to place a dummy patterning device or a patterningdevice-shaped object on said patterning device holder, and tosubsequently rinse the immersion space.
 73. An apparatus according toclaim 61, wherein the apparatus is configured to move said substrateholder with respect to said projection system during the rinsing, suchthat the position of the immersion space changes with respect to thesubstrate holder during the rinsing.
 74. An apparatus according to claim54, wherein the apparatus is configured to start said rinsingautomatically after a predetermined amount of idle time of theapparatus.
 75. An apparatus according to claim 54, wherein the apparatusis configured to start said rinsing automatically after a predeterminednumber of substrate exposures.
 76. An apparatus according to claim 54,wherein the apparatus is configured to determine or estimate whether atleast part of said apparatus has reached a certain threshold amount ofcontamination, and to rinse said apparatus part when it has beendetermined or estimated that said apparatus part has reached thethreshold amount of contamination.
 77. An apparatus according to claim54, further comprising a computer control to control said rinsing. 78.An immersion type lithographic apparatus, including at least one storagespace or compartment to store at least one dummy substrate orsubstrate-shaped object in-situ.
 79. An immersion type lithographicapparatus, including at least one storage space or compartment to storeat least one dummy patterning device or patterning device-shaped objectin-situ.
 80. A computer program containing one or more sequences ofmachine-readable instructions configured to carry out a method forpreventing or reducing contamination of an immersion type projectionapparatus when the computer program is being executed by a computer, theapparatus comprising at least one immersion space that is at leastpartially filled with a liquid when the apparatus projects a beam ofradiation onto a substrate, the method comprising rinsing at least partof the immersion space with a rinsing liquid before the apparatus isused to project the beam of radiation onto a substrate.
 81. A method forpreventing or reducing contamination of a lithographic projectionapparatus comprising a space that is to be provided with a liquidthrough which a beam of radiation can be transmitted, the methodcomprising: operating the lithographic apparatus; and subsequentlyrinsing at least part of the space with a rinsing liquid.
 82. A methodaccording to claim 81, wherein said liquid and said rinsing liquid arethe same liquid.